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S190 Heart Rhythm, Vol. 10, No. 5, May Supplement 2013

Introduction: Atrial fibrillation (AF) results in remodeling of the left atria (LA), alteration of mechanical function and increased risk of thrombus formation and stroke. Limiting ablation to the regions least responsible for mechanical function is advantageous in preserving LA function after ablation. However, the effect of AF on regional mechanical function is not known.Methods: Endocardial surface of the LA in 9 control and 9 patients with paroxysmal AF (PAF) during sinus rhythm were reconstructed from stacked cine MRI images using region growing algorithm. LA was segmented into 5 regions: anterior, posterior, lateral and septal and roof. For each region, regional ejection fraction (REF) was calculated with respect to geometrical center. REF was calculated for total cycle (REF-TC) and for part of the cycle related with active atrial contraction (REF-AC). Velocity of each region was calculated as an average velocity of the surface nodes.Results: REF-TC, REF-AC, mean and instantaneous velocity were significantly higher in control group than in PAF group (p<0.001). A significant regional variation of all parameters was observed (p<0.001), with roof and posterior regions associated with lower function and velocity as compared to anterior, septal and lateral regions (p<0.001).Conclusion:There is considerable difference in regional LA function. Mechanically, anterior, septal and lateral regions are the most active. The roof and posterior regions contribute minimally to atrial mechanical function. In patients with PAF, atrial mechanical function is globally reduced in all regions. Mechanical analysis of 3D model of atria extracted from MRI image may prove to be a valuable tool in LA function assessment.

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EFFECTS OF LIDOCAINE ON GANGLIONATED PLEXI - STUDIES IN THE CANINE AND HUMAN ATRIAL FIBRILLATIONSeungyup Lee, PhD, Albert Waldo, MD, Celeen Khrestian, BS and Jayakumar Sahadevan, MD. Case Western Reserve Univ., Cleveland, OHIntroduction: The role of ganglionated plexi (GP) in the genesis of atrial fibrillation (AF) in the vagal nerve stimulation (VNS) canine model and in patients is not well understood. We hypothesized that blocking neural transmission in the GP by injecting lidocaine into fat pads (FPs) would not only prevent the initiation of AF in the VNS canine model, but also would only prolong atrial electrogram (AEG) cycle lengths (CLs) in patients with persistent AF (PerAF).Methods: In 7 dogs, during right VNS, AF was induced with 3-7 premature atrial beats and sustained for > 5 mins. 1cc of 2% lidocaine was injected into each of 4 FPs (anterior right GP, inferior right GP, superior left GP, inferior left GP) during sinus rhythm. Reinduction of AF was attempted during VNS after lidocaine injection. Also, in patients with PerAF, 1 cc of 2% lidocaine was injected into the same 4 FPs during AF. AEGs were recorded from an array of 48 bipolar electrodes placed on the epicardial surface of Bachmann’s bundle (BB), and

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SPATIAL DISTRIBUTION OF COMPLEX FRACTIONATED ELECTROGRAMS AND ROTOR CONTRIBUTES TO PSEUDO-FLUTTER IN ATRIAL FIBRILLATIONShih-Lin Chang, MD, PhD, YJ Lin, MD, PhD, LW Lo, MD, YF Hu, MD and SA Chen, MD. Taipei Veterans General Hospital, Taipei, TaiwanIntroduction: Atrial fibrillation (AF) sometimes mimics to organized flutter during catheter ablation of AF. However the mechanism and management is unclear.Methods: Three hundred and nineteen patients with recurrent AF originated from PV and 26 patients with recurrent AF from SVC were included in this study. Electroanatomic mapping was performed to identify the origin of AF.Results: The “flutter-like” ECG was more commonly found in patients with recurrent SVC AF compared to those with recurrent PV AF (88.5% vs. 1.3%, P<0.001). Intracardiac recording demonstrated a rapid firing at SVC with conduction block in the rest of the atrium during AF and an organized CS activation sequence in 23/26 patients with recurrent SVC AF. Substrate mapping during SVC AF showed that the highest dominant frequency (DF) site (10.3±1.2 Hz) was located at the SVC and complex fractionated atrial electrograms (CFAEs) with fractional interval of 42±7 msec were presented at the boundary of highest DF site (Figure). Low voltage zone was observed in SVC ostium with mean voltage of 0.38±0.11 mV. Compared to patients with recurrent PV AF originated from pulmonary vein, patients with recurrent SVC AF had a lower voltage (1.1±0.3 mV vs. 1.8±0.8 mV, P<0.0001) and longer total activation time (128±12 ms vs. 109±32 ms, P=0.001) of right atrium. No difference in LA voltage and total activation was found between these two groups.Conclusion: Low voltage zone with CFAEs at highest DF boundaries in SVC ostium could lead to conduction block, which may be responsible for the organized atrial activation sequence and “flutter-like” ECG manifested in SVC AF following catheter ablation. This finding may help ablators to identify the origin of psedo-flutter.

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REGIONAL ASSESSMENT OF ATRIAL FUNCTION IN PAROXYSMAL AF USING 3D MRI GEOMETRY RECONSTRUCTIONPawel Kuklik, PhD, Payman Molae, MBBS, PhD, Anand N. Ganesan, MBBS, PhD, Anthony G. Brooks, PhD, Stephen G. Worthley, MBBS, PhD and Prashanthan Sanders, MBBS, PhD. Centre for Heart Rhythm Disorders, University of Adelaide, Adelaide, Australia

S191Poster Session II

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EFFECT OF RENAL SYMPATHETIC DENERVATION ON THE INDUCIBILITY OF ATRIAL FIBRILLATION AND ATRIAL STRUCTURE REMODELING IN AMBULATORY CANINES OF PROLONGED ATRIAL PACINGXule Wang, MD, Qingyan Zhao, MD, PhD, Jinping Xiao, MD, Zixuan Dai, MD, Shengbo Yu, MD, PhD and Congxin Huang, MD, PhD. Renmin Hospital of Wuhan University; Cardiovascular Research Institute of Wuhan University, Wuchang, Wuhan City, ChinaIntroduction: We have previously demonstrated that catheter-based renal sympathetic denervation (RSD) could suppress atrial fibrillation (AF) during short-term, rapid right atrial pacing (RAP) for 7 hours. However, it is not known whether RSD remains effective for the reduction of AF in canines with prolonged RAP.Methods: Twenty mongrel dogs were implanted with a high frequency cardiac pacemaker inserting a transvenous lead at the right atrial appendage, and were divided into three groups: sham-operated group (n=6), RAP group (n=7) and RSD group (n=7). Sham-operated group dogs were implanted with pacemakers without pacing. In RSD group dogs, a pacemaker was implanted 6 weeks after RSD was performed bilaterally for recovery. Atrial pacing was maintained for 5 weeks in both RAP group and RSD group dogs. Echocardiography and electrophysiological test were measured in all the animals at the baseline and endpoint of the protocol.Results: AF was induced easier in the RAP group than in the sham-operated group and the RSD group after 5 week atrial pacing (P<0.05). AERP was significantly shortened after prolonged atrial pacing from 142±8 ms to 115±9 ms in RAP group (P=0.002). However, the probability value that AERP decreased from 140±10 ms to 127±11ms in RSD group was not significantly different (P=0.087). Echocardiography showed left atrial volume (LAVmax and LAVmin) was significantly reduced in RSD group than in RAP group (P<0.05), although the LAVmax and LAVmin were significantly increased by atrial pacing for 5 weeks compared with values observed before atrial pacing both in RAP group and RSD group. Ultrastructural changes by transmission electron microscopy that severe disintegration of myofilaments, loss of banding pattern and integrity of contractile elements, and mitochondrial swelling with a decrease in the density observed after 5 week atrial pacing were markedly attenuated by RSD. Masson’s trichrome staining of atrial myocardium showed that extensive fibrosis was especially visible in RAP group, but attenuated in the RSD group (CVF of LA, 4.38±1.36% vs 12.26±4.11%, P=0.001; CVF of RA, 5.60±1.35% vs 13.17±3.79%, P=0.004).Conclusion: Catheter-based renal denervation can reduce the incidences of AF and suppress atrial remodelling by prolonged RAP.

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ACUTE RATE OF TRANSMURAL LESIONS INDUCED BY THE EPICOR SYSTEM ® DURING PERI-OPERATIVE LEFT ATRIAL ABLATION FOR ATRIAL FIBRILLATIONJean-Philippe Maury, MD, Amin Bennadji, MD, Bertrand Marcheix, MD, Christophe Cron, MD, Alexandre Duparc, MD, Pierre Mondoly, MD, Anne Rollin, MD, Christelle Cardin, MD, Marc Delay, MD and Yves Glock, MD. Hopital de Rangueil, Toulouse, FranceIntroduction: The Epicor system ® is based on high intensity focused ultrasound (HIFU) energy used for creating a wide circumferential linear left atrial lesion encircling both left atrial

AEGs were recorded for 30 secs prior to and immediately after lidocaine injection. The mean CLs and CL variation (CLV) were measured.Results: AF was not inducible (< 5 secs) in 4 of 7 AF VNS dogs after the injection of lidocaine in all 4 FPs. In 2 patients with PerAF, after injection of lidocaine in to the 4 FPs during AF, AEG CLs of the left atrial (LA) portion of BB prolonged (mean CL: from 179 to 191 ms, from 173 to 191 ms, p < 0.0001 for both), but there was no effect on the right atrial (RA) portion of BB. In one patient, AEG CLs became more regular in the LA portion of BB (CLV from 13 to 10% of the mean CL, p < 0.001).Conclusion: Injection of lidocaine into the FPs decreased inducibility of AF in the canine VNS AF model, and significantly prolonged CL in the LA portion of BB in patients with PerAF. The mechanism of localized AEGs CL prolongation in patient with PerAF is uncertain.

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RELATIONSHIP BETWEEN LOSS OF PACE CAPTURE ALONG THE ABLATION LINE AND RECOVERED CONDUCTION GAPSKoichiro Kumagai, MD, PhD and Hideko Toyama, MD, PhD. Fukuoka Sanno Hospital, Fukuoka, JapanIntroduction: Pace capture along the ablation line can be used to identify conduction gaps during ablation of atrial fibrillation (AF). We investigated the relationship between loss of pace capture along the ablation line and recovered conduction gaps.Methods: Seventy-six patients (60±10 years old) who underwent a second ablation procedure for the recurrent AF were included in the study. At an initial ablation procedure, the pulmonary vein (PV) isolation, left atrial roof and floor linear ablation (box isolation) was performed in all patients. Entrance block of the box lesion was confirmed by lack of potentials in box. After confirming entrance block, lesions were placed until pace capture at 10V no longer occurred along the line to achieve exit block. The endpoint was box isolation (entrance and exit block), that is both lack of potentials in box and loss of pace capture. During a second ablation procedure, the sites with electrical reconnection of PVs and recovered conduction gaps along the linear lesions were detected and compared with those during the initial ablation procedure. The pacing sites along the PV, left atrial roof and floor lines were divided into 40 sites.Results: During an initial ablation procedure, even after entrance block was achieved, additional ablation sites with pace capture were present in 9±9 sites on the ablation line. Of 40 sites, the roof of the right superior PV, the anterior aspect of the left superior PV, and the bottom of the right inferior PV required more radiofrequency applications as compared with other sites to achieve loss of pace capture. All patients reached the endpoints of complete box isolation and loss of pace capture. During a second ablation procedure, electrical reconnection of PVs and recovered conduction gaps were found in 8±8 sites on the line, and most recovered sites corresponded to the sites with pace capture at the initial ablation procedure.Conclusion: Pace capture sites along the ablation line may correspond to the recovered conduction gaps. More radiofrequency ablation energy was required to achieve loss of pace capture along the ablation line than for entrance block. Further study is warranted to determine whether this method results in more permanent lesions that reduce recurrence of AF.


comparable to irrigated RF ablation (646±449; p=0.7). The duration of total procedure as well as time of RF delivery was comparable between “conventional” and “modified” phased RF. Both times were significantly shorter compared to irrigated RF (123±28 vs. 193±36; 15±4 vs. 31±10; p < 0.001 respectively).Conclusion: PVI with ,modified“ phased RF is associated with an decreased number of cerebral microembolism especially during the delivery of ablation impulses, supporting the significance of electrical interference between ablation electrodes 1 and 10. Deactivation of electrode pairs 1 or 5 might increase the safety of this approach without increase in procedure duration or RF delivery time. Further clinical studies are needed to evaluate the efficiency and safety of this “modified“ phased RF PVI.

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ANTIARRHYTHMIC DRUG THERAPY FOR MAINTAINING SINUS RHYTHM EARLY AFTER PULMONARY VEIN ABLATION IN PATIENTS WITH SYMPTOMATIC ATRIAL FIBRILLATIONChristian Sohns, MD, Valerie von Gruben, MD, Samuel Sossalla, MD, Joachim Seegers, MD, Lars Lüthje, MD, Dirk Vollmann, MD and Markus Zabel, MD. Dept. Cardiology and Pneumology University Goettingen, Goettingen, GermanyIntroduction: It is still unclear what is optimal pharmacological treatment of patients early after atrial fibrillation (AF) ablation. We analyzed if concomitant antiarrhythmic drug (AAD) therapy significantly alters the recurrence of AF/ atrial tachycardia (AT) following pulmonary vein ablation (PVA) within the first two months after the ablation procedure.Methods: We analyzed 274 patients with circumferential PVA. For the first two months after PVA patients were individually scheduled for concomitant treatment with beta-adrenergic blocking agents (BB), flecainide, sotalol, dronedarone and amiodarone. All patients were followed in the outpatient clinic after 3 months. The primary end point of this study was a composite of (1) AF/AT lasting more than 24 hours; (2) symptomatic AF/AT recurrence requiring hospital admission, cardioversion, or change of AAD therapy; or (3) intolerance to the specific antiarrhythmic agent given. Uni- and multivariate analysis were performed to evaluate significant predictors for a successful AAD therapy.Results: Early after PVA patients were treated with BB (n=89), flecainide (n=99), sotalol (n=37), dronedarone (n=29) or amiodarone (n=115). A total of 369 observation periods were analyzed. Over the first two months following PVA AF/AT recurrences were found in 42%. No significant difference regarding freedom from AF/AT recurrence according to the different drug therapy was observed (p=0.769). Coronary artery disease, an elevated systolic pulmonary artery pressure and a reduced left ventricular ejection fraction were independent predictors of AF recurrence in univariate analysis. In multivariate analysis using cox-regression with backwards elimination none of the parameters reached the level of significance to predict success of the AAD therapy. In eight observations AAD therapy had to be terminated due to side effects presumably related to the antiarrhythmic agent. These side effects consisted of a skin rash (n=3), severe fatigue (n=2), recurrent severe headaches (n=2), and ongoing nausea (n=1).Conclusion: In the early period after PVA, AAD therapy is not superior to BB treatment in the management of occurring atrial arrhythmias. In the early period after PVA no drug was superior to the others regarding the maintenance of sinus rhythm.

posterior wall and pulmonary veins (box lesion) and provides long-term cure in patients with atrial fibrillation (AFib) undergoing heart surgery. If acute complete disconnection of the box lesion is achieved by application of HIFU is unknown.Methods: bipolar pacing and detection into the box lesion was studied in 13 consecutive pts (9 men, 70 ±9 yo) undergoing heart surgery (8 aortic valve replacement, 4 mitral valve repair or replacement and one coronary by-pass) using bipolar electrophysiological catheter and a real time telemetry (Medtronic CareLink® programmer), just after completion of the ablation process on the beating heart prior to initiation of extracorporeal circulation. AFib was paroxysmal in 8 and persistent in 5. Sinus rhythm was present or obtained using internal cardioversion in each before the ablation process.Results: Mean left ventricular ejection fraction was 60±10 % and mean left atrial area 29±5 cm2. Entrance block was absent in 9 (1 to 1 conduction from sinus rhythm inside the box lesion), undetermined in one and present in 3 (dissociated slow local rhythm). Exit block was lacking in 9 (capture of the cardiac rate by pacing inside the box lesion) and present in 4 (dissociated sinus rhythm from the paced area). Both exit and entrance block were present in only 2 patients. At discharge 5 pts were in sinus rhythm and AFib recurred in 8. At 6 months, 66% with uni/bidirectional block were in sinus rhythm vs 60% without any block (ns).Conclusion: Acute complete block of the Epicor ® HIFU induced box lesion is lacking in the vast majority of pts despite completion of the energy deliverance according to the automated ablation process. Whether block later happens, or whether supplementary applications would increase the electrophysiological and clinical success rate is unknown.

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MODIFIED PHASED RF FOR ABLATION OF ATRIAL FIBRILLATION REDUCES THE NUMBER OF CEREBRAL MICROEMBOLIC SIGNALSStephan Zellerhoff, MD, Martin A. Ritter, MD, Simon Kochhäuser, MD, Julia Köbe, MD, Peter Milberg, MD, Catharina Korsukewitz, MD, Dirk G. Dechering, MD, Christian Pott, CCDS, Kristina Wasmer, MD, Patrick Leitz, Fatih Güner, Lars Eckardt, MD and Gerold Mönnig, MD. Division of Electrophysiology, Department of Cardiovascular Medicine, University of Muenster, Muenster, Germany, Department of Neurology, University of Muenster, Muenster, GermanyIntroduction: Phased RF ablation for atrial fibrillation is associated with an increased number of silent cerebral lesions on MRI imaging and cerebral microembolic signals (MES) on transcranial doppler imaging compared to irrigated RF. The increased rate of embolic events may be due to a specific electrical interference of ablation electrodes attributed to the catheter design. The purpose of this study was to elucidate the effect of deactivating the culprit electrodes on cerebral microembolic signals.Methods: 25 consecutive patients (60±10 years, 9 female) underwent their first PVI using phased RF energy. Electrode pairs 1 or 5 were deactivated to avoid electrical interference between electrodes 1 and 10. Detection of MES by transcranial doppler imaging was used throughout the procedure to assess cerebral microembolism. The results were compared to the rates of MES in 31 patients ablated using all available electrodes and to 30 patients undergoing irrigated RF ablation.Results: Ablation with “modified” phased RF was associated with a marked decrease in MES when compared with “conventional” phased RF (608±329 vs. 1530±980; p<0.001). This difference was mainly triggered by reduction of MES during delivery of phased RF energy, resulting in a MES rate


site and mode and the clinical outcome has not been fully evaluated.Methods: 135 patients (62±9 years) underwent fi rst ablation procedure for PsAF (76 longstanding PsAF). With an endpoint of AF termination, the ablation procedure was performed sequentially in the following order: pulmonary vein antrum isolation (PVAI), left atrial and right atrial substrate modifi cation.Results: AF termination was achieved in 69 (51%) patients (24 in PV antrum, and 45 in atrium) (direct conversion to sinus rhythm in 21, and atrial tachycardia (AT) in 48). With mean 1.7± 0.7 procedures/patient, 100 patients (74%) were free from atrial tachyarrhythmias (ATa) at median 15.0 months follow-up. At the initial procedure, the AF termination site (atrium vs. PV antrum, hazard ratio (HR) =1.38, 95% confi dence interval (CI) 0.72-3.77 and no termination vs. PV antrum, HR=2.32, 95% CI 1.26-6.30; p=0.023) and mode (AT vs. sinus rhythm, HR=1.47, 95% CI 0.77-4.01 and no termination vs. sinus rhythm, HR=2.38, 95% CI 1.26-6.46; p=0.017) were independent predictors of ATa recurrence after the last ablation procedure.Conclusion: The site and the mode of AF termination at the index ablation procedure predict arrhythmia recurrence following multiple catheter ablation procedures for persistent AF.

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CLINICAL CHARACTERISTICS OF PERIESOPHAGEAL NERVOUS INJURY COMPLICATING LEFT ATRIAL ABLATION OF ATRIAL FIBRILLATION: LESSONS FROM 11 CASESTaishi Kuwahara, MD, Atsushi Takahashi, MD, Kenji Okubo, MD, Katsumasa Takagi, MD, Masateru Takagi, MD, Yuji Watari, MD, Emiko Nakajima, MD, Naohiko Kawaguchi, MD, Kazuya Yamao, MD and Kazutaka Aonuma, MD. Yokosuka Kyousai General Hospital, Kanagawa, Japan, Cardiology Division, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, JapanIntroduction: This study aimed to elucidate the clinical characteristics and the management of periesophageal nervous injury complicating catheter ablation of atrial fi brillation (AF).Methods: Extensive pulmonary vein isolation was performed in 3,705 patients with drug-resistant symptomatic AF at our institution. Either non-irrigated or irrigated ablation catheter was used with radiofrequency power of 30 to 40 Watt. Esophageal temperature was monitored in 3,548 patients, and when the esophageal temperature reached 42°C, radiofrequency energy delivery was stopped.Results: Eleven patients (60 ± 11 years, 10 males) were diagnosed as having periesophageal nervous injury after catheter ablation. Symptoms involved nausea, vomiting, abdominal distension and constipation, which occurred within 48 hours after the procedure. Gastrointestinal fl uoroscopy or endoscopy revealed gastric hypomotility (10 patients) and pyloric spasm (1 patient). Metoclopramide, erythromycin or mosapride were effective in relieving symptoms in 5 patients,

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DIFFUSION CEREBRAL MAGNETIC RESONANCE IMAGING (DMRI) PRE AND 24 HOUR AFTER CATHETER ABLATION OF ATRIAL FIBRILLATION UNDER “THERAPEUTIC” WARFARIN: PREVALENCE OF SILENT THROMBOEMBOLIC LESION FROM A PROSPECTIVE MULTICENTER STUDYLuigi Di Biase, MD, PHD, FHRS, Fiorenzo Gaita, MD, Neal Rutledge, MD, Pasquale Santangeli, MD, Rachel (Xue) Yan, BS, Prasant Mohanty, MBBS, Sanghamitra Mohanty, MD, Chintan Trivedi, MD, MPH, Justin Price, BS, Rong Bai, MD, PhD, Rodney Horton, MD, Javier Sanchez, MD, Joe Gallinghouse, MD, Salwa Beheiry, RN, Richard Hongo, MD, Jason Zagrodzky, MD, Davide Castagno, MD, Matteo Anselmino, MD, Elisabetta Toso, MD, Alessandro Blandino, MD, J. David Burkhardt, MD and Andrea Natale, MD. Texas Cardiac Arrhythmia Institute at St. David’s Medical Center, Austin, TX, University of Turin, Turin, Italy, Austin Radiological Association, Austin, TX, California Pacifi c Medical Center, San Francisco, CAIntroduction: Silent thromboembolic lesion (STL) as detected by diffusion cerebral magnetic resonance imaging (dMRI) following catheter ablation of atrial fi brillation (AF) with open irrigated radiofrequency energy (RF) has been reported in 14% of the cases while performing the procedure with warfarin discontinuation. We sought to determine the prevalence of STL while performing AF ablation without warfarin discontinuation with open irrigated RF energy.Methods: Consecutive patients undergoing RF ablation for AF with “therapeutic” warfarin and undergoing heparin bolus before transseptal were included in this prospective multicenter study. All patients underwent pre-ablation and pos-ablation (within 24 hours) dMRI. All patients had to maintain ACT above 300 secs during the entire procedure. During the ablation if sinus rhythm could not be achieved, electrical cardioversion was utilized to restore sinus rhythm.Results: 146 patients (62±9 years, 74% male, paroxysmal 25%, persistent 30%, long-standing persistent 45%, CHADS ≥2 11%) were included. The mean INR was 2.5±0.3. Pre and post-procedural dMRI was obtained in all cases. Sinus rhythm was restored with cardioversion in 35 pts (24%) of the cases. The incidence of post-ablation STL was 2.1% in overall population. When sorting the results by AF type we found that it was 0% (0/37) in paroxysmal patients, 0% in PER pts (0/43) and 4.5% in LSP pts (3/66).At multivariable analysis cardioversion did not show prognostic association with STL (odds ratio 1.9 (0.30 to 13.11), p=.48). All pts with STL had a single brain lesion less < 5 mm.Conclusion: This study shows that if catheter ablation of AF is performed under “therapeutic” warfarin the risk of STL is limited to patients with LSP where extensive ablation was performed. In addition lesions were small and did not correlate with cardioversion.

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IMPACT OF ATRIAL FIBRILLATION TERMINATION SITE AND TERMINATION MODE DURING CATHETER ABLATION ON ARRHYTHMIA RECURRENCEShinsuke Miyazaki, MD, PhD, Hiroshi Taniguchi, MD, PhD, Yuki Komatsu, MD, Takashi Uchiyama, MD, Shigeki Kusa, MD, Hiroaki Nakamura, MD, PhD, Hitoshi Hachiya, MD, PhD and Yoshito Iesaka, MD, PHD, FHRS. Cardiovascular Center, Tsuchiura Kyodo Hospital, Tsuchiura, JapanIntroduction: Although atrial fi brillation (AF) termination has been reported as a predictor of clinical outcome after persistent AF (PsAF) ablation, the relationship between the AF termination


Guro Hospital, Seoul, Republic of Korea, Department of Cardiology, Hallym University Hangang Sacred Heart Hospital, Seoul, Republic of Korea, Utah Valley Regional Medical Center, Provo, UTIntroduction: Although it has been proven that AF burden is significantly diminished after catheter ablation (CA) for atrial fibrillation (AF), discontinuation of oral anticoagulation (OAC) has not been recommended, even though patients had maintained sinus rhythm (SR). The aim of this study was to investigate whether oral antiplatelet (OAP) is safe in patients with SR after successful AF ablation.Methods: 445 patients (age, 56.5±11.6 years; male, 75.3%; persistent AF, 44.7%) who had no evidence of AF recurrence after 3-6 months following successful CA were consecutively enrolled. Of these, 364 subjects (82%) discontinued OAC and then switched with OAP, and 81 (18%) remained on OAC.Results: There were no significant differences in baseline characteristics between OAC and OAP groups, except age (P=0.007), persistent AF (P=0.004), left atrial volume (P<0.001), and CHA2DS2-VASc score (P=0.037). During mean follow-up of 28.0±13.1 months, 2 (0.5%) experienced thromboembolism in OAP group and 2 (2.5%) had major bleeding in OAC group. Kaplan-Meier curve (Figure) showed that there was no significant difference in event-free survival between two groups (P=0.314). In AF patients with CHA2DS2-VASc score ≥ 2, there were no significant differences of thromboembolic and major bleeding incidences (1.2% vs. 4.5%, P=0.141) between two groups.Conclusion: Thromboembolic event was very low during the long-term follow-up period in patients with SR after successful AF ablation. OAP may be a safe regimen, even though patients had CHA2DS2-VASc score ≥ 2.

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INTERRELATIONSHIP BETWEEN THE VEIN OF MARSHALL AND THE ACTIVITY OF THE GANGLIONATED PLEXI IN ATRIAL FIBRILLATIONTakehiko Keida, MD, Masaki Fujita, MD, Masaya Nakata, MD, Tatsuya Yamashita, MD, Marohito Nakata, MD, Toshiyuki Nishikido, MD, Toshiya Chinen, MD, Tatsuo Kikuchi, MD, Kentaro Nakamura, MD, Kentaro Meguro, MD, Hiroshi Ohira, MD and Kaoru Okishige, MD. Edogawa Hospital, Tokyo, Japan, Yokohama City Minato Red Cross Hospital, Yokohama, JapanIntroduction: It has been suggested that autonomic gangionated plexi (GP) adjacent to pulmonary veins (PV) play an important role in triggering and maintenance of atrial fibrillation (AF). Besides the vein of Marshall (VOM) and both myocardial fibers and nerves around it have been implicated as a genesis of AF. Nevertheless, little is known about the interrelation between the VOM and the activity of the GP. To investigate the interrelationship between the VOM and the activity of the GP.Methods: Six patients who underwent both persistent AF

and the patient with pyloric spasm underwent esophagojejunal anastomosis. Eight patients almost fully recovered within 40 days, however, 3 patients had suffered from severe symptoms for 3 to 12 months. This complication occurred in 4 of 157 patients (2.5%) without esophageal temperature monitoring, and 7 of 3,548 (0.2%) patients with esophageal temperature monitoring (p=0.0007). The 3 patients with persistent severe symptoms received no esophageal temperature monitoring.Conclusion: The severity of the periesophageal nervous injury owing to AF ablation varies from mild to severe. Radiofrequency delivery under the esophageal temperature monitoring could reduce its incidence and prevent severe cases of this complication.

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NO ADDITIVE EFFECTS OF ADJUNCTIVE CARNIA ABLATION WITH PULMONARY VEIN ISOLATION FOR PAROXYSMAL ATRIAL FIBRILLATION ON THE RECURRENCE RATEHirosuke Yamaji, MD, PhD, Shunninchi Higashiya, MD, Takashi Murakami, MD, PhD, Hiroshi Kawamura, MD, PhD, Shigeshi Kamikawa, MD, PhD, Masaaki Murakami, MD, PhD and Kazuyoshi Hina, MD, PhD. Okayama Heart Clinic, Okayama, JapanIntroduction: Extensive encircling pulmonary vein (PV) isolation (EEPVI) is now a standard therapy for atrial fibrillation (AF). Efficacy of adjunctive carnia ablation combined with EEPVI on the AF recurrence has not been fully clarified.Introduction: We compared the AF recurrence rate between adjunctive PV carnia ablation with EEPVI and only EEPVI.Methods: A total of 130 patients with paroxysmal AF(1st session) were enrolled (63±9years). After obtaining informed consent, patients were randomized into two groups: adjunctive PV carnia ablation with EEPVI (Group 1, n=65) and only EEPVI (Group 2, n=65). We evaluated the AF recurrence after 3-month.Results: There were no differences in patient clinical characteristics, associated disorders, echocardiographic parameters, or arrhythmia status between the two groups. There were also no differences in complications (such as bleeding, hematoma, pulmonary vein stenosis), (Group1, 3 cases, Group, 2, 2 cases, p=0.66), procedure time (Group1, 102±32min, Group2, 106±34min, p=0.98), fluoroscopic time (Group 1, 29±2.9min Group 2, 30±4.5min, P=0.58) and ablation time(Group1, 33±7 min, Group 2, 31±8 min, P=0.66). AF recurrence rate did not differ between the two groups(Group1 9%, (6/65), Group2, 7%,(7/65) p=0.79).Conclusion: These results showed no additive effects of adjunctive PV carina ablation with EEPVI on AF recurrence rate. Thus complete electrical PV isolation is important to reduce the AF recurrence rate.

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SAFETY OF ORAL ANTIPLATELET THERAPY IN PATIENTS WITH SINUS RHYTHM AFTER SUCCESSFUL CATHETER ABLATION FOR ATRIAL FIBRILLATIONSung Il Im, MD, Hong Euy Lim, MD, PhD, Seung Yong Shin, MD, Seok Man Moon, BS, Jin Oh Na, MD, PhD, Cheol Ung Choi, MD, PhD, Jong Il Choi, MD, PhD, Jin Won Kim, MD, PhD, Hwan Seok Yong, MD, PhD, Eung Ju Kim, MD, PhD, Seong Woo Han, MD, PhD, Sang Weon Park, MD, PhD and Chun Hwang, MD, PhD. Cardiovascular Center, Korea University Guro Hospital, Seoul, Republic of Korea, Cardiovascular Center, Chung-Ang University Hospital, Seoul, Republic of Korea, Cardiovascular Center, Korea University Anam hospital, Seoul, Republic of Korea, Department of Radiology, Korea University


performed in all patients. Critical mass reduction rate (CMR) was defi ned as ratio ISA to total surface area of LA.Results: There were no signifi cant differences between two groups in baseline characteristics such as age, LA volume (LAV), LA surface area, and left ventricular function, etc. Compared with CFAE group, AF termination rate during CA was higher, ablation time were shorter, and CMR was lower in linear group (26.1% vs. 22.4%, respectively, p=0.001). After index procedure, AF recurred in 27 in CFAE group and 16 in linear group (45.8% vs. 26.7%, respectively, p=0.023). In multivariate Cox regression analysis, ablation strategy and LAV were independently associated with arrhythmia recurrence.Conclusion: Compared with CFAE ablation, stepwise linear approach was more effi cient ablation strategy for L-PeAF. Conduction block might be more important to eliminate arrhythmia substrate, rather than CMR itself.

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CRUCIAL AREAS AND CUMULATIVE EFFECT OF COMPLEX FRACTIONATED ATRIAL ELECTROGRAMS ABLATION ON ATRIAL FIBRILLATION TERMINATIONAlexandre Maluski, MD, Julien Seitz, MD, Clement Bars, MD, Jérôme Horvilleur, MD, Jérôme Lacotte, MD, Arnaud Rosier, MD, Ange Ferracci, MD, Jacques Faure, MD, Michel Bremondy, MD, Laurence Curel, MASc, Guillaume Penaranda, PhD and André Pisapia, MD. Saint Joseph Hospital, Marseille, France, Institut Mutualiste Montsouris, Paris, France, Institut Hospitalier Jacques Cartier, Massy, FranceIntroduction: Recent data has demonstrated that focal sources are determinant in human Atrial Fibrillation (AF) perpetuation. We sought to evaluate the cumulative effect of Complex Fractionated Atrial Electrograms (CFAE) ablation on AF Cycle Length (CL) and to identify crucial areas for AF perpetuation.Methods: Patients with refractory AF (n=113, 73% males, 60±10 years, 83% of non paroxysmal) underwent CFAE ablation with AF termination endpoint: conversion to Atrial Tachycardia (AT) or Sinus Rhythm (SR). Ablation points where classifi ed as “crucial”, when they increased the CL over 20% of initial CL, or terminated AF. For AT organisation, focal or linear ablations were performed according to the mechanism of tachycardia.Results: AF was terminated by defragmentation in 108/ 113 patients (95.6%), with SR conversion by ablation in 87/113 (77%). A cumulative effect of defragmentation with progressive increase of AF CL was observed in 97 % (34.9 ± 25.8 ms). We identifi ed 209 crucial points localised into 3 main zones: Mitral Annulus/ peri-LAA, peri-CS ostium and fossa ovalis areas (fi gure). AF was organized in AT in 76 pts, 58 were successfully ablated: 38 macro-circuits (19 peri-tricuspid, 13 peri-mitral, 6 roofs) and 41 foci (9 CS ostium, 6 LAA ridge, 5 inferior LAA root,

ablation (PV antrum ablation) and the VOM cannulation (5 male, aged 65.9±5.6years) were studied. High frequency stimulation (20 V, 20Hz(50ms), 10msec) during AF was applied to the VOM with a multi-electrode catheter to evaluate vagal response. Up to 4 ml 100% ethanol infusion to the VOM was also performed with an angioplasty balloon catheter. Vagal response was reviewed before and after the ethanol infusion of the VOM.Results: Five of the 6 patients showed vagal response before the ethanol infusion of the VOM. After the ethanol infusion, this vagal response disappeared in all the 5 patients.(Fig)Conclusion: This fi nding support that the activity of the GP might be mediated by the VOM and the fi bers and nerves around it.

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DOES THE AMOUNT OF CRITICAL MASS REDUCTION IMPROVE CLINICAL OUTCOME AFTER CATHETER ABLATION IN PATIENTS WITH LONG-STANDING PERSISTENT ATRIAL FIBRILLATION? THE COMPARISON BETWEEN LINEAR ABLATION AND DEFRAGMENTATIONHong Euy Lim, MD, PhD, Seok Man Moon, BS, Sung Il Im, MD, Seung Yong Shin, MD, Jin Oh Na, MD, PhD, Cheol Ung Choi, MD, PhD, Jong Il Choi, MD, PhD, Jin Won Kim, MD, PhD, Hwan Seok Yong, MD, PhD, Eung Ju Kim, MD, PhD, Seong Woo Han, MD, PhD, Sang Weon Park, MD, PhD and Chun Hwang, MD, PhD. Cardiovascular Center, Korea University Guro Hospital, Seoul, Republic of Korea, Cardiovascular Center, Chung-Ang University Hospital, Seoul, Republic of Korea, Cardiovascular Center, Korea University Anam hospital, Seoul, Republic of Korea, Department of Radiology, Korea University Guro Hospital, Seoul, Republic of Korea, 5Department of Cardiology, Hallym University Hangang Sacred Heart Hospital, Seoul, Republic of Korea, Division of Cardiology, Utah Valley Regional Medical Center, Provo, UTIntroduction: Although larger isolated surface area (ISA) of left atrium (LA) may improve the success rate of catheter ablation (CA) for paroxysmal atrial fi brillation (AF), it is still unclear whether the amount of ISA or ablation strategy infl uence clinical outcome after CA in patients with long-standing persistent AF (L-PeAF).Methods: 119 consecutive patients with L-PeAF were randomized into linear ablation and complex fractionated atrial electrograms (CFAE)-guided ablation groups, and followed for 12 months. After circumferential pulmonary vein isolation using NavX system, stepwise linear approach included roof and anterior perimitral ablations with conduction block (n=60). Defragmentation was conducted with high-density automated CFAE mapping in LA (n=59). Cavotricuspid isthmus block was


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OPTIMIZATION OF ELECTROGRAM FILTERING ENABLES ACTIVATION MAPPING OF WAVELETS DURING HUMAN ATRIAL FIBRILLATION - INSIGHTS FROM HIGH DENSITY MULTI-ELECTRODE CONTACT MAPPINGAmir Jadidi, MD, Steve Kim, BSc, Heiko Lehrmann, MD, Chan-il Park, MD, Reinhold Weber, MD, Jochen Schiebeling-Römer, MD, Juergen Allgeier, MD, Pierre Jais, MD, Michel Haissaguerre, MD and Thomas Arentz, MD. Universitaets-Herzzentrum Freiburg Bad Krozingen, Rhythmologie, Bad Krozingen, Germany, SJM, St Paul, MN, Hopital Cardiologique du Haut-Leveque, Pessac-Bordeaux, FranceIntroduction: Activation mapping of AF drivers (sources & rotors) is challenging because of the presence of EGM fractionation & multiple deflections during AF. We assessed the impact of EGM recording and filtering technique on degree of EGM fractionation and ability to map Af wavelets.Methods: Regional AF mapping was performed in 10 pts with persist. AF in uni- & bipolar modes using two 20-pole catheters (AFocus, PentaRay). AF was recorded for 60 sec. EGM fractionation (deflection number) & the ability to map AF wavelet activation were compared between different recordings (uni- vs. bipolar) and filterings (1-25 Hz vs. 30-250Hz and 1-250Hz).Results: Continuous fractionation was found at 38+/-8% vs. 14+/-7% of LA when bipolar CFE maps were created with 30-250Hz vs. 1-25Hz (p<0.01). AF wavelet mapping was feasible at 78+/-11% of mapped regions when filters were set to 1Hz to 250Hz, especially in unipolar recording mode. Conventional EGM filtering (30-250Hz) was associated with high frequency multi-component (fractionated) EGMs that hindered activation mapping of AF. Number of EGM deflections was 2,2 fold higher with bipolar recording (at 30-250Hz) than in unipolar mode at 1-250Hz: (84 +/-16 vs. 34+/-12 deflections per sec AF, p<0,001). EGM filtering at 1-250Hz revealed repetitive regional pivoting and slow conduction channels in AF.Conclusion: Activation mapping of AF wavelets is feasible using high pass EGM filtering from 1Hz instead of 30Hz both in bi- & unipolar recording mode. Regional disparities in conduction with pivoting can be observed. Introduction of these novel EGM filtering methods enables visualization & identification of AF drivers.

3 antero-superior right PV). Mean procedure and fluoroscopic times were 220± 63 min and 22±14.5 respectively.Conclusion: Although CFAE ablation had a cumulative effect on AF with progressive CL increase, crucial areas on its perpetuation have been identified especially around the CS ostium, fossa ovalis, and Mitral annulus/peri-LAA area.

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ADENOSINE-MEDIATED ACUTE PULMONARY VEIN RECONNECTION OCCURS AT REGIONS OF LOW CONTACT FORCEHeiko Lehrmann, MD, Chan-Il Park, MD, Jochen Schiebeling, MD, Jürgen Allgeier, MD, Reinhold Weber, MD, Thomas Arentz, MD, PhD and Amir S. Jadidi, MD. University Heart Center Freiburg Bad Krozingen, Bad Krozingen, GermanyIntroduction: The crucial role of pulmonary veins as drivers of atrial fibrillation has been established and their isolation is one of the steps of AF ablation. Despite high rates of acute pulmonary vein isolation (PVI) during first ablation, PV reconnection is the most common mechanism of ablation failure and AF recurrence. We evaluated if acute spontaneous or Adenosine-induced PV-recovery (PVR) sites correlated to ablation sites with low contact force (CF) or low force-time-integral (FTI), in patients undergoing PVI for AF.Methods: 40 patients with symptomatic AF (33% persistent, 80% male, 61 ± 10 years) underwent wide 3D-guided circumferential PVI with the new SmartTouch™ CF sensing catheter. Patients were ablated with operators being blinded to the CF/FTI data. Acute PVR sites under Adenosine (or during waiting period) as well as acute PV isolation sites were marked on the 3D-map for later comparison to regional CF and FTI data.Results: 153 PV were ablated and isolated from the LA in 40 patients by delivering 2153 points of RF ablation (~14.1 points/vein). We observed 35 PVR sites [63% with Adenosine, 37% spontaneously]. Analysis of acute PVR sites showed significantly lower CF- and FTI-values compared to sites without reconnection: CF 5.1 vs 10.6 g (p < 0.0001), FTI 225 vs 415 gs (p < 0.0001). Nevertheless, in 14% of PVR-sites we observed higher FTI-values, but a low ablation point density as a possible explanation for the occurrence of PVR at those sites.Conclusion: Low contact force during pulmonary vein isolation is the underlying mechanism of Adenosine-mediated acute PV-reconnection in 86%. Prospective use of CF measurements for PVI may significantly reduce the high rates of PV-reconnection.


maintained to achieve an activated clotting time of >300 seconds. After the procedure, warfarin was continued in all patients for 3 months. After 3 months, warfarin and antiarrhythmic drugs were discontinued irrespective of AF type. In patients with CHADS2 score ≥2 (including age≥75 years), prior stroke or transient ischemic attack, or a high risk of recurrence, warfarin was continued despite a successful outcome from ablation.Results: Mean CHADS2 score was 1.1±1.1. The pulmonary vein isolation and left atrial roof and floor linear ablation was performed in all patients. Subsequently, ablation of complex fractionated atrial electrograms was performed in 65% of the patients with non-paroxysmal AF. Ischemic cerebrovascular events occurred in 2 patients (0.28%) within 24 hours of ablation. After a follow-up of 36±10 months (range, 13-56 months), 81% remained AF free without antiarrhythmic drugs. Only one patient (0.14%) in whom warfarin was discontinued (CHADS2 score =1) had an ischemic cerebrovascular event at 9 months after ablation.Conclusion: The risk of a thromboembolic event after successful AF ablation is very low. Discontinuation of oral anticoagulation appears to be safe after successful AF ablation in patients with CHADS2 score <2 (except age≥75 years, prior stroke or transient ischemic attack). Sufficient safety data are as yet unavailable to support discontinuation of oral anticoagulation in patients with a high risk of thromboembolism.

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PERIPROCEDURAL CEREBROVASCULAR ACCIDENTS DURING ELECTROPHYSIOLOGIC PROCEDURES: CHARACTERISTICS, MANAGEMENT AND OUTCOMESSerge Harb, MD, George Thomas, MD, Walid I. Saliba, MD, Georges N. Nakhoul, MD, Ayman A. Hussein, MD, Valeria E. Duarte, MD, Mandeep Bhargava, MD, Bryan Baranowski, MD, Patrick Tchou, MD, Thomas Dresing, MD, Thomas Callahan, MD, Mohamed Kanj, MD, Andrea Natale, MD, Bruce D. Lindsay, MD and Oussama M. Wazni, MD. Cleveland Clinic, Cleveland, OH, NewYork-Presbyterian Hospital, New York, NY, Texas Cardiac Arrhythmia Institute at St. David’s Medical Center, Austin, TXIntroduction: Periprocedural cerebrovascular accident (PCVA) during electrophysiologic (EP) procedures is a feared complication with few data regarding its characteristics and management. We sought to describe the incidence, type [ischemic vs. hemorrhagic, stroke vs. TIA], risk factors, management and outcomes of PCVA in a large cohort of pts undergoing invasive EP proceduresMethods: Between 1998 and 2008, 30.032 consecutive invasive procedures (device implants and ablations) from the Cleveland Clinic EP database were reviewed for PCVA. Events during or within 2 days after the procedure were included. Diagnosis was based on stroke team assessment and brain imaging. Pts with PCVA were compared to 100 randomly selected controls with no PCVA from the same databaseResults: We identified 38 CVAs: 20(53%) were intraprocedural and 18(47%) postprocedural; 32(84%) were strokes and 6(16%) TIAs. All CVAs except one (37, 97%) were ischemic and most (36, 95%) occurred during ablation procedures. Compared to controls, pts with CVA were older (p=0.04), more likely to be males (p=0.04), had lower Ejection Fraction [EF] (p=0.02) and were more likely to have a history of Atrial Fibrillation [Afib] (p=0.01) or a previous episode of stroke (p=0.03) - Table 1. Among the 31 pts with ischemic stroke, 11 (35%) received reperfusion (8 catheter based and 3 IV t-PA) of whom 5(46%) had complete recovery, 3(27%) had partial recovery and 3(27%) had no recovery. No hemorrhagic transformations occurredConclusion: PCVA during EP procedures is rare and almost always ischemic. It occurs more frequently during ablation procedures and among older male pts with low EF and history of

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REVEALING DORMANT CONDUCTION WITH ADENOSINE AFTER CRYOBALLOON ABLATION REDUCES AF-RECURRENCE AT MID-TERM FOLLOW-UPMarieke Compier, MD, Katja Zeppenfeld, MD, PhD, Marta de Riva Silva, MD, Katia M. Dyrda, MD, Martin J. Schalij, MD, PhD and Serge A. Trines, MD, PhD. Leiden University Medical Center, Leiden, NetherlandsIntroduction: Pulmonary vein isolation (PVI) is an important treatment modality for atrial fibrillation (AF). Repeated procedures are often necessary due to electrical reconnection of the pulmonary veins (PVs). Dormant conduction (DC) can be revealed after radiofrequency ablation by infusion of adenosine. This study evaluated the incidence of DC after cryoballoon ablation and the effect of unmasking DC and performing additional ablation on the efficacy of cryoballoon ablation.Methods: Patients with paroxysmal or persistent AF scheduled for a first ablation procedure were included. PVI was performed with a 23 or 28 mm cryoballoon catheter (Arctic Front, Medtronic, Minneapolis, USA), depending on PV size. At least two 5-minute applications were performed for each vein. Thirty minutes after PVI, a12-24 mg bolus adenosine was injected to establish DC for each vein. In case of unmasked DC, additional applications with cryoenergy were performed until DC was absent. A control group that underwent cryoballoon ablation without adenosine infusion was selected. The number of applications and time-to-isolation of the PV and freeze temperature were registered. Efficacy of ablation was established after 3 and 6 months follow-up with ECG and 24-hour Holter recordings.Results: Consecutive patients were included for cryoablation with adenosine (n=30) and compared to patients treated with cryoablation without adenosine (n=68). During the procedure, DC was found in 43% of patients (13/30) and 15% of the PVs (18/119). After a mean follow-up of 7±1 months, a reduced number of patients (20%) had AF-recurrence after ablation with DC testing, compared to 38% after cryoablation only (p<0.05). Univariate analysis indicated three predictors of DC: time-to-isolation of the PV (p<0.01), PV isolation during the first freeze (p<0.01) and minimum freeze temperature (p=0.058). After multivariate analysis, PV isolation during the first freeze was found to independently reduce the risk of DC (OR=0.06, p<0.01).Conclusion: Detection of dormant PV conduction with adenosine and subsequent abolishing of DC improves outcome of cryoballoon ablation in patients with AF at mid-term follow-up. Absence of PV isolation during the first freeze was associated with an increased risk of dormant conduction.

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RISK OF THROMBOEMBOLISM AND NEED FOR ORAL ANTICOAGULATION AFTER SUCCESSFUL CATHETER ABLATION OF ATRIAL FIBRILLATIONKoichiro Kumagai, MD, PhD and Hideko Toyama, MD, PhD. Fukuoka Sanno Hospital, Fukuoka, JapanIntroduction: Discontinuation of oral anticoagulation after catheter ablation of atrial fibrillation (AF) is controversial. The safety of this management strategy in patients without recurrent AF remains unknown. The aim of this study was to evaluate the safety of discontinuing oral anticoagulation after successful AF ablation.Methods: AF ablation was performed in 727 consecutive patients (61±10 years old) with paroxysmal (n = 494), persistent (n = 96), or longstanding persistent (n=137) AF. All patients received dose-adjusted warfarin (international normalized ratio, 2.0-3.0) for 3 months before the procedure. Warfarin was continued throughout the procedure. During the procedure, heparin infusion was


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RANOLAZINE FOR THE SUPPRESSION OF VENTRICULAR ARRHYTHMIAS: A CASE SERIESEric Yeung, MD, Mori J. Krantz, MD, Joseph Schuller, MD and Mark C. Haigney, MD. Walter Reed National Military Medical Center, Bethesda, MD, Denver Health Medical Center, Denver, CO, Uniformed Services University of the Health Sciences, Bethesda, MDIntroduction: Frequent premature ventricular contractions (PVCs)and ventricular tachycardia (VT) are associated with persistent symptoms and worsening ventricular function. Medical therapy with beta-blockers and approved antiarrhythmics can have undesirable side effects and proarrhythmic liability. Ranolazine preferentially blocks the late sodium (Na) current, a depolarizing conductance which may destabilize repolarization in ischemia and heart failure. Blockade of the late Na current is a potentially attractive approach for subjects with high burdens of PVCs or VT unresponsive to beta blockade.Methods: We retrospectively evaluated 8 patients with ventricular arrhythmias (6 with >10% PVC burden and 2 with refractory VT) treated with ranolazine. Arrhythmia burden was assessed by Holter monitoring before and after the initiation of oral ranolazine at 500-1000 mg twice daily.Results: Among the 6 patients with PVCs, ranolazine therapy resulted in a mean reduction in PVC burden of 53% (p=0.047, Table). In 2 cases of apparent PVC-induced cardiomyopathy, normalization of ventricular function was observed. A significant inverse relation between ejection fraction and percentage change in PVCs was present (r=-0.81, p=0.0497). In 2 patients treated for VT storm despite Class III anti-arrhythmic therapy, ranolazine successfully suppressed VT and prevented recurrent ICD therapy.Conclusion: Although not approved by the FDA for arrhythmia suppression, ranolazine appears to be an effective therapy for symptomatic ventricular arrhythmias. The effect was greatest in those individuals with reduced left ventricular function, perhaps due to enhanced late Na current associated with their cardiomyopathy. Ranolazine in patients with PVC and VT

Age Indication Ejection Fraction %

Pre Ranolazine #PVC

Post Ranolazine #PVC

% PVC Reduction

66 PVC 35- 40 28,800 0 100.00%75 PVC 45- 50 20,939 3,547 83.06%27 PVC 55- 60 37,708 32,969 12.57%71 PVC 60- 65 21,044 21,306 -1.25%61 NSVT 40- 45 42,500 26,611 37.39%54 NSVT/PVC 20- 25 56,129 5,400 90%60 Recurrent VT 30- 35 Incessant Zero VT episode Not Applicable66 Recurrent VT 25- 30 Incessant One VT episode Not Applicable

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THE SIGNIFICANCE OF PSEUDO DELTA WAVES IN IDIOPATHIC VENTRICULAR ARRHYTHMIAS WITH A LEFT BUNDLE BRANCH BLOCK AND INFERIOR AXIS MORPHOLOGYMaged F. Nageh, MD, Prabhat Hebbar, MD, Jonathan Turner, MD, Sen Ji, MD, Nigel Gupta, MD, Jonathan Doris, MD, Joseph Wu, MD, Simon Kangavari, MD and Michael Lee, MD. Kaiser Permanente Medical Center, Dept. of Electrophysiology-Regional Arrhythmia Center, Los Angeles, CAIntroduction: Ventricular Tachycardia (VT) with left bundle branch block (LBBB)/inferior axis morphology accounts for up to 70% of idiopathic VT (iVT), and can originate from the Right (RVOT) or Left ventricular outflow tracts (LVOT) as well as

AFib and stroke. Reperfusion therapy is feasible and safeTable 1 - Cases vs. Controls CharacteristicsCharacteristic CVA (N=38) No CVA (N=100) P valueAge, mean (SD), years 60(12.5) 55(14) 0.04Male % 84 67 0.04Hypertension % 42 40 0.82Diabetes Mellitus % 10.5 11 0.94Hyperlipidemia % 50 47 0.75AFib % 87 66 0.01Stroke history % 13 3 0.03INR, mean (SD) 1.4(0.4) 1.6(0.6) 0.27EF, mean (SD) 46(15) 51(13) 0.02

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INCIDENCE OF SILENT CEREBRAL LESIONS USING DIFFERENT ABLATION TECHNOLOGIESThomas Deneke, MD, Joachim Krug, MD, Karin Nentwich, MD, Jacek Majewski, MD, Rainer Schmitt, MD, Patrick Müller, MD, Andreas Mügge, MD, Marc Horlitz, MD, Dong-In Shin, MD, Martin Bansmann, MD and Anja Schade, MD. Heartcenter Bad Neustadt, Bad Neustadt, Germany, Heartcenter Bergmannsheil Bochum, Bochum, Germany, Heartcenter Cologne-Porz, Cologne, GermanyIntroduction: Cerebral lesions (SCL) have been detected on post interventional magnetic resonance imaging (MRI) in asymptomatic patients after atrial fibrillation (AF) ablation procedures. The present study evaluates incidence and potential contributing factors for SCL in a large cohort of patients undergoing radiofrequency (RF), endoscopic laser balloon (EAS) or cryo-balloon (CB) ablation of AF.Methods: Patients eligible for pre- and post-ablation MRI were included. Patients underwent AF ablation using cooled-tip single-tip RF (group 1), multipolar phased RF (group 2), EAS (group 3) or CB (group 4) ablation. MRI was performed before, after and in cases of detected SCL 2 to 6 weeks after ablation. All ablations were carried out according to a standardized protocol under heparinization with ACTs > 300seconds. SCL were defined as new onset lesion with hyperintense signal in diffusion weighted imaging and hypointense signal on apparent diffusion coefficient map.Results: A total of 247 patients were included and no patient had acute cerebral lesions identified on pre-ablation MRI. On post-ablation MRI 85 patients (35%) had a total of 234 SCLs (2.7/pt). 20% of group 1, 41% of group 2, 37% of group 3 and 21% of group 4 patients had documented SCLs. When dividing group 2 into patients only undergoing pulmonary vein isolation (PVI) using the PVAC 39% (50 out of 128) had SCL and 78% (11 out of 14) undergoing PVI plus additional phased RF ablations had SCLs. Within group 1: 2.3 SCL/pt, group 2: 2.6/pt in PVI alone and 4.7/pt in PVI plus, in group 3: 2.3lesions/pt and in group 4 2.3/pt were identified. During follow-up of 2 to 6 weeks only 5 lesions (2% of SCLs) (all >10mm diameter) were still identified on MRI and all other lesions were not detected any more. No pre-ablation parameter was identified to be a significant predictor of SCL occurrence.Conclusion: SCL may be identified in a substantial portion of patients undergoing AF ablation. Incidence of SCL may vary according to the technology used. The incidence and number of lesions appears to be highest using phased RF PVI plus additional left atrial phased RF ablations. 98% of lesions appear to resolve in follow-up MRI and only large lesions (>10mm) may cause cerebral scarring. Variable MRI-definitions and -technology may cause differences in incidences of SCLs.


groups (968±51 vs. 916±47ms), however, baseline QTc was significantly longer in 17 LQT3 patients than 15 LQT1+LQT2 patients (561±15 vs. 513±16msec; p=0.04). While the QTc was abbreviated with mexiletine in both groups, the QTc shortening (ΔQTc) was more remarkable in LQT3 patients than in LQT1+LQT2 patients (105±9 vs. 44±9msec; p<0.0001, Figure). The sensitivity and specificity for differentiating LQT3 patients from LQT1+LQT2 patients were 82% and 93%, respectively, when the best cut-off value of 75msec of ΔQTc, which was calculated by receiver operating characteristic curve. The predictive accuracy of this study was 88%.Conclusion: Mexiletine infusion test is useful to predict the genotype of LQT3 syndrome.

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CLINICAL AND ELECTROCARDIOGRAPHICAL CHARACTERISTICS ASSOCIATED WITH RECURRENT VENTRICULAR ARRHYTHMIAS IN EARLY REPORALIZATION SYNDROMEKensuke Ihara, MD, Yoshihide Takahashi, MD, PhD, Akihiko Nogami, MD, PhD, Mitsuhiro Nishizaki, MD, PhD, Kaoru Okishige, MD, PHD, FHRS, Kenzo Hirao, MD, PhD, Mitsuaki Isobe, MD, PhD, the J-PREVENT registry investigators. Heart center, Yokohama-city Bay Red Cross Hospital, Kanagawa, Japan, Department of Cardiology, National Disaster Medical Center, Tokyo, Japan, Department of Heart Rhythm Management, Yokohama Rosai Hospital, Kanagawa, Japan, Department of Cardiology, Yokohama Minami Kyosai Hospital, Kanagawa, Japan, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan, Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, JapanIntroduction: Early repolarization (ER) on electrocardiography (ECG) is associated with increased risk of idiopathic ventricular arrhythmia or sudden cardiac death (SCD). Although implantable cardioverter-defibrillator (ICD) therapy is the cornerstone of secondary prevention of SCD, the reduction in ICD shocks is desired with respect to quality of life. We sought to characterize the patients who had recurrences of ventricular arrhythmias in the patients with ER syndrome.Methods: Case subjects were enrolled from the J-PREVENT registry which was the multicenter registry of idiopathic ventricular fibrillation from 12 emergency hospitals in Japan. In ER patients, more than 0.1 mV elevation at the J point above baseline had to be observed in at least 2 leads other than the anterior precordial leads. The patients with Brugada type ECG with or without sodium channel blocker were excluded, and those with short or long QT syndrome were also excluded from this study. ECGs recorded on the day of the successful resuscitation or during the hypothermic treatment were excluded in the assessment of daily valiance of J wave. Recurrences of cardiac events were defined as appropriate defibrillator therapies or SCD. Clinical and electrocardiographical characteristics in the patients with recurrent cardiac events were evaluated.

other contiguous structures. EKG criteria for localization were established by several investigators.Methods: The records of all patients referred for Radiofrequency ablation (RFA) of iVT between 2009-2012 were reviewed, and their EKG features were examined and correlated to the successful site of RFA. A total of 53 patients with LBBB-iVT were identified. Positive delta waves (DW) in leads V1-V2 were detected in 11/53 patients (figure shows examples from 3 patients).Results: Electroanatomic activation and pace mapping of RVOT were performed in all patients. RVOT RFA was successful in 39/50 patients (RFA deferred due to proximity to His (2 patients) and left main artery/LVOT (1 patient). RVOT mapping did not reveal early activation sites or identical pace match in any of the 11 patients with DW compared to 42 patients without DW.In patients with DW, the LVOT and Anterior interventricular vein branch (AIV) of the Coronay sinus were mapped in 8 and 6 patients respectively. AIV had the earliest activation electrograms (-35 to - 45 milliseconds), and pacematch scores of 11/12. RFA within the AIV was limited by low flow in spite of using open irrigation catheter.Conclusion: In our cohort of patients, the presence of DW was a highly sensitive marker for non RVOT focus of VT and correlated with an epicardial origin within the AIV in those patient in whom it was mapped. Careful examination of the 12 lead EKG can facilitate the mapping process and predict the outcome of the RFA procedure.

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DIAGNOSTIC VALUE OF MEXILETINE INFUSION TEST FOR DETECTING TYPE 3 CONGENITAL LONG QT SYNDROME (LQT3)Moritoshi Funasako, MD, Ikutaro Nakajima, MD, Koji Miyamoto, MD, Yuko Yamada, MD, Hideo Okamura, MD, Takashi Noda, MD, Kazuhiro Satomi, MD, Takeshi Aiba, MD, Shiro Kamakura, MD, Toshihisa Anzai, MD, Masaharu Ishihara, MD, Satoshi Yasuda, MD, Hisao Ogawa, MD, Yoshihiro Miyamoto, MD and Wataru Shimizu, MD. National Cerebral and Cardiovascular Center, Osaka, JapanIntroduction: Mexiletine, an IB sodium channel blocker, is often used for medical therapy in LQT3 patients. However, the diagnostic value of mexiletine infusion test for LQT3 patients has not yet been reported. Aim of this study was to evaluate the diagnostic value of mexiletine infusion test for detecting LQT3 patients.Methods: We retrospectively analyzed the responses of 12-lead electrocardiographic parameters measured in V5 leads to intravenous mexiletine infusion (2 mg/kg) during sinus rhythm among 32 genotype-positive LQT patients (29±18 y.o., 12 males). The corrected QT interval (QTc) before and after mexiletine infusion was investigated in 17 LQT3 patients (24±19 y.o., 9 males), and compared to that in 15 LQT1+LQT2 patients (4 LQT1 and 11 LQT2) (34±14 y.o., 3 males).Results: Baseline RR interval was not different between 2


Chest pain 6% Alcoholic liver disease 5% Fibro-fatty infiltration in right ventricle 100%

Vomiting, gastrointestinal upset 3% Hypertension 3% Fibro-fatty infiltration of left ventricle 10%

Dyspnea 3% Diabetes 1% Mean right ventricle thickness <3mm 10%

Cough and sore throat for hours 2% Valvular heart

disease 1% Left anteriordescending myocardial bridging 5%

Dizziness 1% Right ventricle free wall rupture 2%

Abdominal pain 1% Significant coronary arterydisease 1%

PO02-148

RELATION OF COMBINED UNIPOLAR AND BIPOLAR VOLTAGE MAPS TO VENTRICULAR TACHYCARDIA ABLATION OUTCOMES IN ISCHEMIC CARDIOMYOPATHYNagesh Chopra, MD, Timothy G. Campbell, BS, Michifumi Tokuda, MD, Justin Ng, MD, Tobias Reichlin, MD, Eyal Nof, MD, Roy M. John, MD, PhD, Usha B. Tedrow, MD and William G. Stevenson, MD. Brigham and Womens Hospital, Boston, MA, Biosense-Webster, Diamond Bar, CAIntroduction: MR imaging shows that infarct scars causing VT can extend deep to and beyond bipolar low voltage areas (LVA) and may be a source of ablation failure. We hypothesized that the size of the unipolar LVA beyond the overlying bipolar scar may predict outcome of endocardial VT ablation.Methods: Twenty consecutive patients with ischemic cardiomyopathy (all male, age 68±10yrs, LVEF 29±9%, 10 anterior infarcts) who underwent endocardial VT ablation were retrospectively reviewed. Bipolar (filtered at 30-500 Hz) LVA defined as <1.5 mV and unipolar (filtered at 0.5-500 Hz) LVA defined as <8.3mV were reviewed on an electro-anatomic mapping system. VT isthmus sites were identified from entrainment mapping, VT termination by ablation, or pace-mapping with abolition of VT by ablation.Results: All bipolar LVAs (70.5±4.5cm2) had unipolar LVAs that encompassed the bipolar LVA (147±11cm2) and extended beyond it. The unipolar LVA penumbra around the bipolar LVA had an area of 77±9 cm2 and was not different between anterior and inferior/posterior scars (66.6±12 vs. 87±13; p=0.2, Student’s-t). A mean of 3.1±0.3 VTs/patient were induced. Ablations were confined to bipolar LVAs. Following ablation all inducible VTs were abolished in 14 patients, modified in 4 patients and ablation failed to abolish VT in 2 patients. The size of the unipolar penumbra did not differ between these groups. During 3 months follow-up 8/20 patients had VT recurrence. The size of the LVA penumbra was not different for those with (88±17cm2) vs. without (69±10cm2) recurrences. However, all (8/8) of the group that recurred had isthmus/exits in the bipolar LVA border compared to only 3/12 of the group that did not recur, the remainder of whom had isthmus/exits identified within the bipolar LVA area (100% vs. 25%; p<0.05, Fischer-exact).Conclusion: In ischemic cardiomyoapthy, unipolar LVA penumbra of varying size surrounds endocardial bipolar LVA, consistent with MR imaging, indicating intramural/epicardial arrhythmia substrate. In this pilot study, the size of this area did not predict early recurrence after endocardial ablation. Frequent recurrences after VT isthmus/exits ablation at scar periphery is consistent with the possibility of deeper substrate towards the infarct border.

Results: Of 110 patients in the J-PREVENT registry, this study included 25 patients with ER (mean age 42 +/- 15 years, 21 males), all of whom had experienced cardiac arrest and received ICD implantation. No patient had structural heart disease. During a mean follow up of 4.0 years, 10 patients (40%) had experienced recurrences. The patients with recurrences were significantly younger (33.9 +/-13.1 vs 45.7+/- 13.3, p=0.02) and had significantly lower resting heart rate (61 vs 78 bpm, p=0.01) than those without recurrences. Of 21 patients in whom ECG had been recorded routinely during follow up, the daily variation of J wave amplitude was significantly larger in the patients with recurrences than the others (0.17 vs 0.08 mV, p=0.003)Conclusion: Age, resting heart rate, electrocardiographical changes over time in J wave are associated with recurrences of cardiac events in ER syndrome patients.

PO02-147

CHARACTERISTICS OF FORENSIC BIOPSY-PROVEN ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY DEATHS IN TAIWAN: A STUDY OF 98 CONSECUTIVE PATIENTSChih-Hsin Pan, MD, Yenn-Jiang Lin, MD, PhD, Eric Chong, MD, Fa-Po Chung, MD, Yun-Yu Chen, BS, Kai-Ping Shaw, MD and Shih-Ann Chen, MD. Institute Of Forensic Medicine, Ministry of Justice, New Taipei City, Taiwan, Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, Division of Cardiology, Department of Medicine, Taipei Veterans General Hospita, Taipei, TaiwanIntroduction: The purpose of our study was to describe the unique clinical presentations, autopsy features and toxicology findings of Arrhythmogenic right ventricular cardiomyopathy (ARVC) patients who presented as natural sudden cardiac deaths (SCD) from registry of the National Forensic Institute, Taiwan.Results: The mean patient age was 37.5±13.8 (range 13-71) years. Male (N=76,77%) was the predominate gender. All patients suffered from SCD as the first presentation of life. Confirmed history of activities just before death was available for 61 patients. Among them, 3 (5% of known history) were doing active physical exercise during collapse; 9 (14%) were ngaging in non-exertion day-time activities; 48 (79%) were found dead in bed during sleep; 3 (5%) died during day time nap and the remaining during night time sleep. Most patients (84%) were asymptomatic before death and had no past medical history (90%). Autopsy data (Table) showed that the mean heart weight was 366±72 (170-600) g with 2 cases of tamponade resulting from RV free wall rupture. RV myocardium was replaced by abundant fibroadipose tissue in all patients. Blood and urine toxicology analysis showed detectable alcohol levels (>50 mg/dl) in 51 patients (52%) who also had corresponding drinking history within 24 hours. The mean blood alcohol levels were 143±55 (50-237) mg/dl.Conclusion: Our study showed unique clinical presentations of SCD in ARVC patients. Patients frequently had limited warning symptoms and no underlying disease before death. Cardiac rupture could be the cause of death rather than ventricular arrhythmia. Toxicology analysis demonstrated that alcohol might be a trigger for death from malignant arrhythmia.

Table:Clinical manifestation

Symptoms immediately before death % Underlying

disease % Autopsy finding %

No symptoms 84% No underlying disease 90% Right ventricle myocardium loss in

microscopic examination 100%


vivo study in human beings is rare. Meanwhile, whether the preferential conduction also exists during idiopathic left ventricle tachycardia (ILVT) is not clearly defined.Methods: Twenty-five consecutive patients with ILVT entered for electrophysiological study and catheter ablation. In whom, the Left HPS and LV were reconstructed by mapping the antegrade presystolic potentials (PPs) and ventricle potentials respectively. Then, the left HPS and LV were remapped during ILVT by recording the retrograde PPs and ventricle potentials respectively.Results: During SR, antegrade depolarization of left HPS occurred before any LV myocardium with a shorter activation time of left anterior fascicle (LAF) than left posterior fascicle (LPF) (22.0±4.1ms VS 30.0±3.2ms, P<0.001), while the LV septum was depolarized retrogradely. During ILVT, the earliest retrograde PPs were located at the predefined LPF with an average of 15.6±3.9 mm (10~23.1) away from its distal end, and the earliest retrograde PP ratio averaged 0.5±0.1(0.46~0.58, CI: 95%). The LPF was depolarized from the earliest retrograde PP via two opposite wavefronts with significantly shorter activation time (15.1±2.1 VS 30.0±3.2ms P<0.001). The LAF was depolarized after LPF with an antegrade activation sequence and comparable activation time to that during sinus rhythm (21.9±2.9 VS 22.0±4.1ms, P=0.13). Ventricle depolarization occurred after left HPS with retrograde depolarization sequence. Via ablation at the earliest retrograde PPs (in 23 patients with inducible VT) and the middle segment of LPF (in 2 patients with non-inducible VT), no patients reported recurrence after an average of 13±2 months follow up.Conclusion: Via electroanatomical mapping, the main branches of left HPS could be successfully reconstructed. During SR, the HPS exhibited preferential conduction by documenting reverse activation sequence with its surrounding myocardium. During ILVT, the earliest PPs were usually clustered at the middle segment of LPF, and the preferential conduction within the HPS remained.

PO02-151

ASSOCIATION OF FAT DEPOSITION AFTER MYOCARDIAL INFARCTION ON CARDIAC COMPUTED TOMOGRAPHY WITH ELECTROGRAM FEATURES IN PATIENTS WITH ISCHEMIC SCAR-RELATED VENTRICULAR TACHYCARDIASTakeshi Sasaki, MD, PhD, Hugh Calkins, MD, Christopher F. Miller, MS, Rozann Hansford, MPH, Menekhem M. Zviman, PhD, Joseph E. Mairine, MD, David Spragg, MD, Alan Cheng, MD, Harikrishna Tandri, MD, Sunil Sinha, MD, Aranvindan Kolandaivelu, MD, Singo Maeda, MD, PhD, Yasuaki Tanaka, MD, Yasuhiro Yokoyama, MD, PhD, Kenzo Hirao, MD, PhD, David A. Bluemke, MD, PhD, Ronald D. Berger, MD, PhD, Henry R. Halperin, MD, Saman Nazarian, MD, PhD and Stefan L. Zimmerman, MD. Tokyo Medical and Dental University, Tokyo, Japan, Johns Hopkins University, Baltimore, MD, Johhns Hopkins University, Baltimore, MD, Johns Hopkins University, Tokyo, MD, Jonhs Hopkins Universtiy, Baltimore, MD, National Institute of Health, Bethesda, MDIntroductions: Myocardial fat deposition has been observed in infarcted regions of patients with chronic ischemic cardiomyopathy (ICM). The association of local electrogram features on electroanatomic mapping (EAM) with fat deposition has not been investigated. We aimed to quantitatively assess the association of fat deposition on cardiac computed tomography (CT) with local electrograms in patients with ICM.Methods: CT was performed in 16 patients with ischemic ventricular tachycardias (VT) before catheter ablation. EAM points were registered to corresponding CT images using

PO02-149

3D DELAYED ENHANCEMENT MAGNETIC RESONANCE SEQUENCES IMPROVE CONDUCTING CHANNEL DELINEATION PRIOR TO VENTRICULAR TACHYCARDIA ABLATIONDavid Andreu, MSc, Antonio Berruezo, MD, PhD, José T. Ortiz, MD, PhD, Juan Fernández-Armenta, MD, Diego Penela, MD, Elena Arbelo, MD, PhD, José M. Tolosana, MD, Lluís Mont, MD, PhD and Josep Brugada, MD, PhD. Arrhythmia Section, Cardiology Department, Thorax Institute. Hospital Clinic, Universitat de Barcelona., Barcelona, Spain, Cardiology Department, Thorax Institute. Hospital Clinic, Universitat de Barcelona., Barcelona, SpainIntroduction: Delayed enhanced cardiac magnetic resonance using 2D sequences (CMR-2D) represents the standard for clinical characterization of myocardium. However, 2D images suffer from insufficient spatial resolution in the Z-axis and missregistration that preclude appropriate visualization of conducting channels (CC), which are critical for ventricular tachycardia (VT) ablation. We studied whether characterization using a free breathing 3D delayed enhanced navigator gated sequence (CMR-3D) proved to be superior than CMR-2D sequences.Methods: We included 30 consecutive patients with structural heart disease referred for VT ablation. Myocardial characterization was conducted prior to the ablation procedure in a 3T-scanner using CMR-2D and CMR-3D sequences, yielding a spatial resolution of 1.4 x 1.4 x 5 mm and 1.4 x 1.4 x 1.4 mm respectively. The scar components, core and border zone (BZ), were quantified in both datasets using the 60% and 40% threshold of maximum pixel intensity, respectively. The signal to noise ratio (SNR) and contrast to noise ratio (CNR) was analyzed in a representative slice in both sequences. For both set of images a 3D reconstruction of the scar was obtained and an electrophysiologyst identified potential CC and compared them to those depicted in the electroanatomic map (EAM).Results: We found no significant differences between the mass of the scar core in the 2D and 3D sequence (mean 7.33±6.56 vs 6.74±5.22 grams respectivelly, p=0.612). However, the BZ mass was smaller in the 2D than in the 3D sequence (9.38±7.72 vs 12.10±7.81 grams; p=0.019). The SNR was higher in the 2D dataset as compared to the 3D (42.93±27.34 vs 28.09±12.85; p=0.005) as well as the CNR (37.01±26.20 vs 20.15±11.41; p=0.001). The mean number of CC identified in the 3D dataset was higher than in the 2D, and closer to those depicted in the EAM (1.06±0.75 for CMR-2D vs 2.63±1.41 for EAM, p=0.005; and 2.06±1.25 for CMR-3D vs 2.63±1.41 for EAM p=0.088).Conclusion: Despite the higher SNR and CNR of standard CMR-2D images, the higher spatial resolution provided by CMR-3D images improved the overall delineation of CC prior to VT ablation.

PO02-150

PREFERENTIAL CONDUCTION WITHIN THE LEFT HIS-PURKENJE SYSTEM DURING SINUS RHYTHM AND IDIOPATHIC LEFT VENTRICLE TACHYCARDIA: FINDINGS FROM MAPPING THE WHOLE CONDUCTION SYSTEMDe Yong Long, MD, Jian-Zeng Dong, MD, Cai Hua Sang, MD, Chen Xi Jiang, MD, Ri Bo Tang, MD and Chang Sheng Ma, MD. Beijing AnZhen Hospital, Capital Medical University, Beijing, ChinaIntroduction: Functionally, His-Purkenje system (HPS) is insulated from the adjacent myocardium, and exhibits preferential conduction during sinus rhythm (SR), but in


0.5 (P=0.06). However, 6 (30%) of the 20 CC-VA patients had a discrete pre-potential with an isoelectric line between the 1st and the 2nd component, as shown in the Figure, and in comparing these 6 CC-VA patients with the d-GVC patients, although average activation times at the successful ablation site were 59 ± 14 (range 50-84) ms vs. 45 ± 17 ms (P=0.16), average PM scores were signifi cantly lower (3.2 ± 4.6 vs. 11.6 ± 0.5; P=0.003), and excellent PM was shown in only 1 (17%) of these 6 patients.Conclusion: In CC-VA with a discrete pre-potential, activation mapping may take priority over PM, especially when a discrete pre-potential with activation time of ≥50 ms is recognized.

PO02-153

TRANSMURAL ACTIVATION AND REPOLARISATION GRADIENTS EXACERBATED BY INCREASED CHOLINERGIC TONE: A NON-CONTACT MAPPING STUDY OF BRUGADA SYNDROMEJustine Bhar-Amato, MRCP, Sanjay Chaubey, FRCS, Malcolm Finlay, MRCP, Xiao Jie, PhD, Lei Xu, PhD, Martin Lowe, PhD, FRCP, Edward Rowland, MD, FRCP, Oliver Segal, MRCP, Anthony Chow, MRCP, Ron Simon, MRCP and Pier Lambiase, PhD, MRCP. University College London, London, United Kingdom, Kings College London, London, United Kingdom, The Heart Hospital, UCLH, London, United KingdomIntroduction: Conduction & repolarisation heterogeneity is thought to drive arrhythmogenicity in Brugada syndrome (BrS), with increased cholinergic tone enhancing ST elevation & VT risk. We recorded activation & repolarisation in RVOT epicardium (epi) & endocardium (endo) simultaneously & assessed the effect of increased cholinergic tone.Methods: A non-contact mapping array was deployed in the RVOT of 7 BrS & 7 control patients. A CS catheter recorded adjacent epi signals. Restitution curves were constructed pre & post edrophonium (Edr). Multilevel modelling was used to analyse the data.Results: A small control ARI (activation-repolarisation interval) transmural gradient (TMG) was seen (mean 3.4 ms, 95% CI 6.8, 0.02, p<0.05), endo ARIs shorter than epi (fi g 1a). A larger TMG existed in BrS, (mean 20.5 ms, 95% CI 25.5, 15.5,p<0.001) with shorter epi ARIs. Post Edr, both TMGs increased, controls (mean 16 ms 95% CI 19.6,12.6, p<0.001) due to epi ARI prolongation and BrS (mean 29.7 ms, 95% CI 35.3, 24.1, p<0.001) due to endo ARI prolongation. Baseline epi max restitution slopes were steeper (p<0.05) in BrS (mean 0.887, SEM 0.065) compared with controls (mean 0.728, SEM 0.046). BrS epi was activated earlier than endo (mean TMG 15 ms, 95% CI 11, 20, p<0.001)

custom software. Mean Hounsfi eld units (HU) were assessed on short axis CT planes. The association of regional mean HU with electrogram bipolar and unipolar amplitudes and duration was investigated. Regional mean HU was measured in each of 20 sectors per CT short-axis plane.Results: A total of 1662 EAM points were analyzed. Of All EAM points, 532 points (32.7%) were located in regions with fat deposition. Signifi cant differences were observed in mean HU (23.0±37.5 vs. 81.7±21.9, P<0.001), bipolar (0.7±0.6 vs 2.6±2.1 mV, P<0.001) and unipolar (3.3±1.9 vs 7.2±4.0 mV, P<0.001) amplitudes, duration (115±33 vs 82±22 ms, P<0.001) and LV wall thickness (5.0±1.7 vs 7.7±2.2 mm, P<0.001) between the regions with and without fat deposition. In pooled analyses, lower mean HU was strongly associated with lower bipolar and unipolar amplitudes (Figure, P<0.0001, respectively). Mean HU in all regions with >200 msec of electrogram duration ranged between 0 and 60 HU.Conclusion: Electrogram features on endocardial EAM are associated with regional mean HU on CT in patients with ICM. Fat deposition may alter the substrate of post infarct scar-related VT.

PO02-152

DOES ACTIVATION MAPPING TAKE PRIORITY OVER PACE MAPPING IN EPICARDIAL OUTFLOW TRACT VENTRICULAR ARRHYTHMIAS?Hitoshi Hachiya, MD, Kenzo Hirao, MD, Takashi Uchiyama, MD, Shigeki Kusa, MD, Hiroaki Nakamura, MD, Shinsuke Miyazaki, MD, Hiroshi Taniguchi, MD and Yoshito Iesaka, MD. Cardiology Division, Cardiovascular Center, Tsuchiura Kyodo Hospital, Tsuchiura, Japan, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, JapanIn outfl ow tract ventricular arrhythmias (OT-VA), detailed mapping, including both activation and pace mapping (PM), leads to a successful ablation. However, the optimal ablation site is not always both the best activation mapping and the best PM site. We examined which mapping method should take priority in epicardial OT-VA.Methods: In 335 patients from 2 institutions, we experienced 5 (1.5%) patients with distal great cardiac vein (d-GCV) OT-VA and 20 (6%) patients with coronary cusp ventricular arrhythmia (CC-VA).Results: Average activation times at the successful ablation site in the CC-VA versus d-GCV patients were 49 ± 13 ms vs. 45 ± 17 ms (P=0.6), and average PM scores were 6.9 ± 5 vs. 11.6 ±


ablation was performed 2 ±3 months after LVAD placement. In the 6 pts with no VT prior to HM2 implantation, VT began to occur 6 ±2.5 months after implantation. At 12 months, 4 pts were transplanted and 5 died. Of the remaining 8 pts, 5 were arrhythmia free. In 1 pt with VT recurrence, change of turbine speed from 9400 to 9000 rpm extinguished VT.Conclusion: Catheter ablation of VT is effective among LVAD recipients. Intrinsic myocardial scar, rather than the apical cannula, appears to be the dominant substrate.

PO02-155

CATHETER ABLATION OF PREMATURE VENTRICULAR CONTRACTIONS IMPROVES LEFT VENTRICULAR DIASTOLIC FUNCTIONMehmet Akkaya, MD, David G. Benditt, MD, Henri Roukoz, MD, Ahmet S. Adabag, MD, Deviprasad Venugopal, MD, Jian M. Li, MD, Marina Zakharova, MD, Andrew Peter, No Degree and Venkat N. Tholakanahalli, MD. University of Minnesota Medical Center, Minneapolis, MN, Minneapolis VA Medical Center, Minneapolis, MNIntroduction: It is well known that catheter ablation of premature ventricular contractions (PVCs) improves systolic performance of left ventricle (LV) in certain subset of patients, however the effect on diastolic function is unclear. We assessed the effects of catheter ablation of PVCs on parameters of LV diastolic function.Methods: Forty-seven patients (65.2±9.6 years, 46 men) underwent catheter ablation for symptomatic PVCs, were evaluated by two-dimensional echocardiography before and 6±2 months after ablation. The diastolic indices measured were pulsed-wave and tissue Doppler measurements, which included mitral inflow parameters (E wave, A wave, E/A ratio and deceleration time [DT]), mitral lateral annulus early diastolic velocity (Ea) and E/Ea ratio. Left atrial (LA) volume was measured using modified biplane Simpson’s method and we calculated LA maximum volume (LAmax), LA minimum volume (LAmin) and LA volume index (LAVI).Results: After catheter ablation of PVCs, LVEF increased significantly (42.8±11.8 vs 49.9±10.3, p<0.01). Significant improvement was also seen in A wave measurement (59.5 ± 15.1 vs 71.3 ± 17.1 cm/s, p=0.039), E/A ratio (1.42± 0.6 vs 1.07 ± 0.5 ml, p=0.034), Ea (6.8 ± 2.9 cm/s vs 8.9± 3.9, p=0.04) and E/Ea ratio (15.4 ± 5.8 vs 10.6 ± 3.4, p=0.027) at follow-up, whereas mitral E and DT did not show significant change. LAmax (101± 40 vs 83 ± 33 ml, p<0.001) and LAmin (66± 24 vs 43 ± 19 ml, p<0.001) were decreased significantly after ablation accompanied by reduction in LAVI (44.4 ± 14.8 vs 36.7 ± 12.5, p<0.001).

(fig 1b). In controls, epi was activated later (mean TMG 26 ms, 95% CI 21, 32, p<0.001). Edr increased BrS epi & endo conduction velocity, maintaining the TMG.Conclusion: There is a significant endo to epi ARI TMG in BrS, exacerbated by increased cholinergic tone, which preferentially prolongs endo ARI. Earlier epi activation, a shorter epi ARI & endo conduction delay causes an endo to epi repolarisation gradient that could explain the J point elevation seen in BrS.

PO02-154

CHARACTERISTICS OF VT ABLATION IN PATIENTS WITH CONTINUOUS FLOW LEFT VENTRICULAR ASSIST DEVICESFrederic Sacher, MD, Tobias Reichlin, MD, Erica Zado, PA, Michael E. Field, MD, Juan Viles Gonzales, MD, Kabir Bhasin, MD, Kenneth Ellenbogen, MD, Francois Picard, MD, Laurent Barandon, MD, Philippe Ritter, MD, Joachim Calderon, MD, Nicolas Derval, MD, Arnaud Denis, MD, Richard Shepard, MD, James 0. Coffey, MD, Fermin Garcia, MD, Meleze Hocini, MD, Usha Tedrow, MD, Srinivas R. Dukkipati, MD, Michel Haissaguerre, MD, Andre d’Avila, MD, William G. Stevenson, MD, Francis E. Marchlinski, MD and Pierre Jais, MD. Hôpital Cardiologique du Haut Leveque / Université Bordeaux 2, Bordeaux, France, Brigham and Women Hospital, Boston, MA, Hospital of the University of Pennsylvania, Philadelphia, PA, University of Wisconsin, Madison, WI, University of Miami, Miami, FL, Mount Sinai Hospital, New York, NY, Virginia Commonwealth University School of Medicine, Richmond, VAIntroduction: Left ventricular assist device (LVAD) use is increasing as a bridge to cardiac transplant or as destination therapy. These patients are at high risk for ventricular arrhythmias. This study describes VT characteristics and ablation in these patients.Methods: A retrospective review was performed of patients from 5 tertiary EP centers with a Heart Mate 2 (HM2) LVAD who underwent ventricular tachycardia (VT) catheter ablation.Results: Seventeen patients (14 male, age 57 ±11 years) underwent 19 ablation procedures with 3D electroanatomic system. The mean LVEF before HM2 implantation was 17 ±7% with a mixture of ischemic (n=8) and non-ischemic (n=9) etiologies. Twenty-eight VTs (CL 280-740ms, arrhythmic storm in 8) and 2 VF triggers were targeted (12 transseptal, 7 retrograde aortic). Eight pts required VT ablation < 1 month after HM2 implantation due to intractable VT. Only 10% of the targeted ventricular arrhythmias were related to the HM2 cannula site with ablation performed 9 ±6 months after HM2 placement. In the remaining pts in whom VT was not related to the cannula,


PO02-157

THE RARE TYPE OF PERICARDIAL REFLECTION ON THE RIGHT SIDE -CARDIAC STRUCTURE RELATED TO CATHETER MAPPING-Osamu Igawa, MD, PhD, Hirotsugu Atarashi, MD, PhD, Yoshiki Kusama, MD, PhD, Eitaro Kodani, MD, PhD, Reiko Okazaki, MD, PhD, Naomi Kawaguchi, MD, PhD, Kyoichi Mizuno, MD, PhD and Masamitsu Adachi, MD, PhD. Nippon Medical School TamaNagayama Hospital, Tama, Japan, Sanin Rosahi Hospital, Tama, JapanIntroduction: The aim of this study was to study the manner of pericardial reflection especially on the right side, which makes the heart fix to the posterior mediastinum, and to speculate the relation to cardiac movement.Methods: The aspect of pericardial reflection around right pulmonary veins and inferior vena cava were examined in 237 consecutive autopsied hearts (112 Males 76+/-9y.o.) without organic heart diseases. According to the manner of pericardial reflection, all hearts were classified on the base of cardiac fixation pattern.Results: As shown in figure, all hearts were divided into two types of pericardial reflection. In the Type2- pericardial reflection, the pericardium between superior and inferior right pulmonary veins belongs to the oblique sinus of pericardium. In the Type1- pericardial reflection, this area belongs to the right side pericardium. Many of the hearts showed Type1- pericardial reflection, and only two hearts Type2- pericardial reflection.Conclusion: Judging from the fixation pattern, we should take these findings into consideration in catheter mapping to avoid complications associated with catheter manipulation.

PO02-158

PROCEDURAL ENDPOINTS IN CATHETER ABLATION OF VENTRICULAR TACHYCARDIA: SHOULD ALL INDUCIBLE VENTRICULAR TACHYCARDIA BE TARGETED IN ALL PATIENTSArian Sultan, MD, Jakob Lüker, MD, Boris Hoffmann, MD, Helge Servatius, MD, Benjamin Schäffer, MD, Jana Nührich, MD, Doreen Schreiber, MD, Thomas Rostock, MD, Mathias Knoll, MD, Stephan Willems, MD and Daniel Steven, MD. University Heart Center Hamburg, Department of Electrophysiology, Hamburg, Germany, University Hospital Mainz, Department of Electrophysiology, Hamburg, Germany, Robert-Bosch-Krankenhaus Stuttgart, Stuttgart, GermanyIntroduction: Catheter ablation (CA) of ventricular tachycardia (VT) in patients (pts) with structural heart disease (SHD) has become a cornerstone in treatment of VT. Procedure endpoints predicting ablation success have not been established so far. Programmed ventricular stimulation (PVS) frequently reveals

Conclusion: Catheter based treatment of PVCs improves diastolic function of left ventricle and impaired diastolic function may be a potential therapeutic target for catheter ablation.Conventional, Doppler and Tissue Doppler echocardiographic variables before and after PVC ablation

Preablation Postablation P valueMitral E velocity (cm/s) 84.3±29.2 78.7±26.4 0.42Mitral A velocity (cm/s) 59.5±15.1 71.3±17.1 0.039E/A ratio 1.42±0.6 1.07±0.49 0.034Deceleration time (ms) 247±80 228±77 0.73Ea lateral (cm/s) 6.8±2.9 8.9±3.9 0.04E/Ea ratio 15.4±5.8 10.6±3.4 0.027LAVmax, ml 101±39.7 83.4±32.7 <0.001LAVmin, ml 66±23.7 43.4±18.7 <0.001LAVI 44.4±14.8 36.7±12.5 <0.001

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COMPARISON OF VENTRICULAR TACHYCARDIA INDUCIBILITY WITH AND WITHOUT GENERAL ANESTHESIAEyal Nof, MD, Tobias Reichlin, MD, Thomas Tadros, MD, Justin Ng, MD, Roy John, MD, PhD, Douglas Shook, MD, Michifumi Tokuda, MD, Usha Tedrow, MD, MPH, Wendy Gross, MD and William G Stevenson, MD. Brigham and Womens, Boston, MAIntroduction: The effects of general anesthesia (GA) on the inducibility and hemodynamics of ventricular tachycardia (VT) are not clear.Methods: Studies were performed in 40 consecutive pts with heart disease , ICD and prior VT who were undergoing radiofrequency ablation (RFA) {age 64±15; LVEF 36±13%; 50% Ischemic (ICMP)}. Pts underwent non invasive (NI) programmed stimulation (PS) using their ICD while awake. After induction of GA {27/40 (67%)- inhalational agents, 8/40 (20%) - propofol , 5/40 (13%)- combined} and prior to RFA, they underwent invasive RV programmed stimulation (IPS). Endpoint for PS was induction of sustained monomorphic VT (SMVT).Results: In 4 pts (10%) no SMVT was inducible before or after GA. Of the 36 inducible pts pre-GA, 6 (16%) were not inducible after GA (p=0.03). Of the 30 inducible pts before and after GA , 17 (57%) needed a more aggressive PS to induce VT after GA. In 20/30 (67%), the same VT was induced before and after GA and in 10/30 (33%) a different VT was induced after GA. GA more frequently rendered VT not inducible or changed inducible VT morphology in ICMP pts (12/19, 63%) compared to NICMP (4/17, 24%; p=0.02). Other baseline characteristics (LVEF, age, presentation with VT storm, anti-arrhythmic drugs at time of procedure) were not predictive of change in inducibility after GA. After GA, 24/30 (80%) pts received pharmacologic hemodynamic support. In 12/ 30 (40%) pts, VT was hemodynamically stable before and after GA. In 14/30 (47%) pts, VTs were hemodynamically unstable before and after GA. Only in 4/30 pts (13%) were VTs stable before and unstable after GA (2 with the same QRS morphology and 2 with a different QRS morphology). Type of anesthesia agent did not predict VT stability. There were no complications associated with NIPS or IPS after GA.Conclusion: Inducibility of VT does not seem to be impaired by GA for the majority of patients with structural heart disease. In patients with ICMP, NIPS should be considered prior to initiation of GA if confirmation of inducible VT and acquisition of an ECG demonstrating VT is desirable. Adjunctive hemodynamic support with phenylephrine during GA, does not significantly alter stability of VT.


Results: All patients received antiarrhythmic drugs and 34 patients received steroid therapy. During a 49±36 month follow-up, 23 (62%) patients were free from any VT episodes with medical therapy. The ejection fraction and prevalence of a Gallium-67 uptake was lower in those with VT recurrence than in those without (40±12% vs. 54±16%; p<0.05, 22% vs. 91%; p<0.001, respectively). Multivariate Cox regression analysis revealed that absence of gallium-67 myocardial uptake was an independent predictor for VT recurrence under the drug therapy (Hazard ratio, 7.81; 95% confidence interval, 1.70 to 35.84; p<0.01). Fourteen patients who experienced VT recurrences even while on drug therapy underwent RFCA. An electrophysiological study revealed that the mechanism of VT could be classified into 2 subgroups that were Purkinje related VT and scar related VT. The VT-QRS duration was narrower in Purkinje related VT than in scar related VT (149±13 ms vs. 181±26 ms; p<0.01). After a mean follow up of 30±20 months, 6 of 14 patients experienced VT recurrences. The number of induced and sustained VTs was higher in the patients with VT recurrences than in those without (6.2±2.5 vs. 2.7±0.8; p<0.05, 4.0±1.4 vs. 2.0±0.8; p<0.01, respectively).Conclusion: Comprehensive therapeutic approach of VT associated with cardiac sarcoidosis successfully suppressed VT recurrences in the majority of the patients.

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ELECTROANATOMICAL SUBSTRATE-GUIDED CATHETER ABLATION OF VENTRICULAR TACHYCARDIA: IS ADDITIONAL ACTIVATION MAPPING REQUIRED TO IMPROVE RESULTSCorrado Carbucicchio, MD, Gennaro Izzo, MD, Valeria Volpe, MEng, Nadeem Ahmad Raja, MD, Martina Zucchetti, MD, Antonio Dello Russo, MD, PhD, Michela Casella, MD, PhD, Massimo Moltrasio, MD, Benedetta Majocchi, MD, Fabrizio Tundo, MD, PhD, Claudio Tondo, MD, PhD, Luigi Di Biase, MD, PhD and Andrea Natale, MD. Univ. of Milan - Centro Cardiologico Monzino, Milan, Italy, Texas Cardiac Arrhytmia Institute at St David’s Medical Centre, Austin, TX, Texas Cardiac Arrhythmia Institute at St David’s Medical Center, Austin, TXIntroduction: Advanced mapping techniques efficiently guide complex ventricular tachycardia (VT) ablation by identifying putative arrhythmogenic sites in sinus rhythm: the adjunctive value of activation mapping (AMap) has not been elucidated. We sought to define the role of AMap in patients with structural heart disease undergoing electroanatomical substrate-guided ablation of VT.Methods: We prospectively enrolled 89 patients (age 66.2±11.9, ejection fraction 37.6±11.0%) with ischemic (64) or idiopathic (25) dilated cardiomyopathy undergoing endocardial or endo-epicardial electroanatomical mapping and ablation of hemodynamically tolerated and non-tolerated VT(s). The efficacy of AMap was assessed with respect to VT suppression when predefined safety criteria were met. A substrate-guided ablation strategy targeting surrogate markers of reentry was accomplished in all patients; an epicardial approach was required in 15. VT-free survival at one year was assessed by ICD interrogation.Results: AMap successfully guided ablation in 51/82 patients (62.2%) with inducible VT(s). At one year, 5/89 patients (5.6%) died; VT recurred in 18/89 (20.2%). No significant difference in VT recurrence rate was observed between patients in whom AMap proved effective versus those who were treated only by a substrate-guided ablation strategy (10/51, 19.6% versus 8/38, 21.1%; p: ns).Conclusion: Our findings support the efficacy of a substrate-guided ablation strategy targeting specific markers of arrhythmogenicity identified during sinus rhythm. AMap was

VT different from clinical morphologies (cVT). In a retrospective 5-year analysis of procedures for VT ablation influence of different procedure endpoints such as noninducibility (NI) for VT or NI for cVT was analyzed.Methods: In 126 consecutive pts with SHD (114 men, age 65 ± 12 years (y), left ventricular ejection fraction (LV-EF) 33 ± 14 %; ICD n=120) CA for VT was performed. A total of 265 (77%) VT of 345 induced VT were targeted. If not presenting in VT PVS was performed and cVT was identified according to ECG documentation. If hemodynamically stable mapping and CA was attempted during VT in case of unstable VT pts underwent a substrate modification. Successful CA of cVT (group 1) or NI for any VT (group 2) were procedural endpoints. Interrogation of ICD, outpatient visits and 24h-holter ECG were used to assess long-term success.Results: A total of 160 ablation procedures inducing 345 VT (VT cycle length (VTCL) 410 ± 97 ms) were performed (procedure time 199 ± 71 minutes (min), fluoroscopy time 22±13 min). In 65 (41%) procedures CA endpoint consisted of NI of the cVT as opposed to 95 (59%) in whom CA was continued until NI for any VT was achieved (group 2) (substrate based CA n=16; CA during VT=79). Inducibility was tested using PVS with up to three extrastimuli. After long-term FU (25±18.2 months) no significant difference in VT recurrence rate was detected between both groups (26% group 1 vs. 37% group 2; p=0.8). Subanalysis after 4 y revealed a tendency for higher freedom of VT in group 1 (p=0.08). Accordingly, pts in group 1 showed a more preserved LV-EF (37% vs. 31%;(p=0.02)) and slower VTCL of cVT (440±105 ms vs. 420±103 ms; p=0.23).Conclusion: Displayed data show that solely CA of cVT as procedural endpoint for VT ablation is not inferior to CA of all inducible VT with regard to long-term success rates. In selected pts with monomorphic VTs and limited substrate CA of cVTs only may result in satisfactory outcomes. However, in pts with multiple documented cVTs an extended ablation approach should be preferred.

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THE CLINICAL EFFECT OF COMPREHENSIVE THERAPEUTIC APPROACH OF VENTRICULAR TACHYCARDIA ASSOCIATED WITH CARDIAC SARCOIDOSIS: A MULTICENTER COOPERATIVE STUDY FOR THE EVALUATION OF THE THERAPEUTIC IMPACTS OF VENTRICULAR ARRHYTHMIASYoshihisa Naruse, MD, Hiroyuki Okada, MD, Yasuteru Yamauchi, MD, Yukio Sekiguchi, MD, Takeshi Machino, MD, Kenji Kuroki, MD, Yoko Ito, MD, Hiro Yamasaki, MD, Miyako Igarashi, MD, Hiroshi Tada, MD, Junichi Nitta, MD, Akihiko Nogami, MD and Kazutaka Aonuma, MD. University of Tsukuba, Tsukuba, Japan, Musashino Red Cross Hospital, Musashino, Japan, Saitama Red Cross Hospital, Saitama, JapanIntroduction: Ventricular tachycardia (VT) and sudden death are commonly observed in cardiac sarcoidosis, however, the clinical effects of comprehensive therapeutic approach are still uncertain.Methods: We enrolled consecutive 37 patients (56±11 years, 11 men) with a diagnosis of sustained VT associated with cardiac sarcoidosis. All patients were initially treated with corticosteroids and antiarrhythmic agents unless they refused to take them. If the VTs recurred even on the antiarrhythmic and steroid therapy, radiofrequency catheter ablation (RFCA) was performed. Patients who underwent RFCA before being medicated, including with corticosteroids and antiarrhythmic agents, were excluded from this study. The clinical impact of both a steroid and antiarrhythmic therapy associated with RFCA was evaluated.


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CONTACT FORCE RADIOFREQUENCY ABLATION CATHETER WITH LOW IRRIGATION FLOW RATE - RELATIONSHIP BETWEEN LESION DEPTH AND CONTACT FORCE-POWER-TIME INDEX IN THE CANINE BEATING HEARTAtsushi Ikeda, MD, PhD, Hiroshi Nakagawa, MD, PhD, Garth Constantine, MS, Assaf Govari, PhD, Christopher J. Birchard, BSc, Tushar Sharma, MPH, Jan V. Pitha, MD, PhD, Ralph Lazzara, MD and Warren M. Jackman, MD. University of Oklahoma Health Sciences Center, Heart Rhythm Institute, Oklahoma City, OK, Biosense Webster, Inc., Diamond Bar, CA, Biosense Webster, Inc., Tirat-Hacarmel, IsraelIntroduction: A new catheter, combining a contact force (CF) sensor and 56 irrigation holes with low saline irrigation flow rate (IRG) (ThermoCool SmartTouch SF, Biosense Webster, Inc), was used to test whether controlling CF, RF power and application time (Force-Power-Time Index, FPTI, Grams X Watts X Sec) can predict lesion depth and steam pop in the beating canine heart.Methods: 3 dogs were studied closed chest. The 7.5F CF sensing catheter has a tiny spring connecting the 3.5 mm, 56 holes irrigated tip electrode to the shaft. CF (resolution <1g in bench tests) and direction are measured every 25 ms by the degree of spring bending, using a magnetic transmitter (on the tip) and 3 location sensors (shaft). A continuous 1 sec average CF is displayed on the 3D map (CARTO 3). The irrigated CF ablation catheter was positioned in the RV and LV under fluoroscopy. RF was delivered at 25 W (IRG 8 ml/min) to 9 RV sites and at 40 W (IRG 15 ml/min) to 9 LV sites in each dog (total 18 RFs). 3 different ranges of CF: low (4-14 g, median 9 g), moderate (17-29 g, median 21 g), and high CF (31-45 g, median 41 g) and 3 RF times (15, 30 and 60 sec) were used for the 9 RFs in each chamber to obtain wide range of FPTI (1,998 - 98,040). Dogs were sacrificed at 2 hours and RF lesion size was measured.Results: Lesion depth correlated highly with the FPTI (r=0.85, p<0.001, Fig A). Incidence of steam pop significantly increased with increasing FPTI for values >22,150. Electrode temperature and impedance decrease were poor predictors for lesion depth (Figs B and C).Conclusion: This new catheter provides CF and thrombus protection with low IRG flow rate. Controlling FPTI predicts lesion size and incidence of steam pop in the beating canine heart.

effective in most patients but did not contribute to a higher VT-free survival, suggesting that in patients with advanced cardiac disease life-threatening arrhythmias can be effectively treated by ablation in sinus rhythm, thus limiting procedural risks.

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NEUROHORMONAL, STRUCTURAL AND FUNCTIONAL RECOVERY PATTERN AFTER PREMATURE VENTRICULAR COMPLEX ABLATION IN PATIENTS WITH DEPRESSED LEFT VENTRICULAR EJECTION FRACTION, INDEPENDENTLY OF STRUCTURAL HEART DISEASEDiego Penela, MD, Antonio Berruezo, MD, PhD, Katja Zeppenfeld, MD, PhD, Luis Aguinaga, MD, Juan Fernández-Armenta, MD, Carine Van Huls Vans Taxis, MD, Lluis Mont, MD, PhD, Csaba Herczku, MD, PhD and Josep Brugada, MD, PhD. Arrhythmia Section, Cardiology Department, Thorax Institute. Hospital Clínic, Universitat de Barcelona, Barcelona, Spain, Department of Cardiology, Leiden University. Leiden, The Netherlands, Leiden, Netherlands, Centro Privado de Cardiología, Tucuman, Argentina, Argentina, Argentina, Institute of Cardiology, University of Debrecen, Debrecen, Hungary., Hungary, HungaryIntroduction: The aim of the study was to assess the clinical benefit and the recovery pattern after premature ventricular complex (PVC) ablation in consecutive patients with frequent PVCs and left ventricular (LV) dysfunction, with or without a diagnosis of structural heart disease (SHD).Methods: Consecutive patients with frequent PVCs and LV dysfunction were prospectively included. The left ventricular ejection fraction (LVEF), NYHA functional class and brain natriuretic peptide (BNP) levels were evaluated before and at 1, 6 and 12 months after radiofrequency ablation (RFA). Successful sustained ablation (SSA) was defined as a persistent decrease of at least 80% of PVC burden during follow-up.Results: Eighty patients completed the follow-up, 27 (34%) of whom had previously diagnosed SHD. SSA was achieved in 53 (66%) patients. After SSA, LVEF improved from 33±8% to 43.6±9.5% to 45.8±11% at 6 and 12 months, respectively (p <0.05). BNP decreased from 274±309 pg/mL to 78±108 pg/mL to 58± 104, pg/mL to 37±47 pg/mL at 1, 6 and 12 months, respectively (p<0.05). NYHA class improved from 2±0.7 to 1.69±0.5 to 1.3±0.3 to 1.1±0.3 at 1, 6 and 12 months, respectively (p <0.05). Comparing patients with and without previous SHD, there were no differences in echocardiographic response (p=0.781), clinical response (p=0.68) or BNP reduction (p=0.27) after RFA. A 13% baseline PVC burden had a 100% sensitivity and 85% specificity to predict an absolute increase of at least 5% in LVEF, after SSA. In 21 (78%) of the 27 patients with class I indication for primary prevention implantable cardioverter-defibrillator (ICD) and more than 13% PVCs at baseline the indication was removed after the ablation attempt, most often within the first 6 months (17 patients, 81%).Conclusion: SSA ablation of frequent PVC in consecutive patients with depressed LVEF induced a progressive clinical and functional improvement regardless of the presence of previous SHD, which continued during the 12-month follow-up. The benefit is directly related to baseline PVC percentage.


create similar lesions with the same heat transfer. The purpose of this study was to independently compare, by a thermographic technique, the tissue heat transfer of 4 open-irrigated Cs.Methods: RF applications were performed on bovine LV sections in a heparinized blood bath (37oC) with blood flow circulating at 0.2 m/s. RF was delivered (n=33) for 60s at 20W (irrigation 17 mL/m) using Biosense Thermocool (TC, n=8), SJM CoolFlex (CF, n=8), Boston Scientific Blazer Open-Irrigated (BOI, n=8) and Biosense Surround Flow (SF, n=9). RF was applied perpendicularly to the endocardial surface at the edge of the preparation. Applications were filmed using an infra-red thermal camera (Fluke, Ti-10). Maximum (Tmax) temperature (T) was determined from all pixels and the T-depth relation was calculated from 12 equidistant points, 1mm spacing, along a perpendicular line from the electrode-tissue interface. Area of tissue with T>50ºC (A50) was calculated at 60s.Results: We found no relevant differences comparing Tmax or A50 among TC, BOI and CF. However, the SF tended to show lower Tmax than the rest (TC: 71±10, BOI: 68±10, CF: 65±7 and SF: 56±11ºC; p=0.09). A50 was significantly lower using SF as compared with TC applications (58±90 mm2 Vs 300±204 mm2; p=0.03). This was mainly due to a lower 3 mm-depth T with SF (42±6 ºC) than with the TC (62±14ºC; p=0.025) and the BOI (58±13ºC; p=0.07). At 7mm-depth no significant differences were found comparing the 4 Cs. In fact, Tmax was registered at 5±3.3, 5.3±1.8 and 5.7±3.2mm-depth using TC, BOI, CF (pNS) and significantly deeper with the SF (10.2±2.7mm; p=0.01).Conclusion: Despite technological differences, heat transfer is relatively similar using TC, BOI and CF. However, at 17ml/m, the SF produces a higher surface cooling than the rest of the analyzed Cs, delivering most of the heat to deeper areas. This data supports halving its flow rate for conventional ablation substrates, and may support its use at 17ml/m when lesion depth is needed rather than superficial damage, as in aortic cusps or coronary sinus ablation.

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RISK STRATIFICATION OF VENTRICULAR TACHYCARDIA OR VENTRICULAR FIBRILLATION IN POSTINFARCTION PATIENTS WITH EF≤35%: RESULTS FROM A MULTICENTER ICD RISK STRATIFICATION STUDYWojciech Zareba, MD, PhD, James Daubert, MD, Otto Costantini, MD, Aysha Arshad, MD, Jean Philippe Couderc, PhD, Andrew E. Epstein, MD, Scott McNitt, MS, Arthur J. Moss, MD, Eric Rashba, MD, Spencer Rosero, MD, Lawrence S. Rosenthal, MD, PhD, Stephen R. Shorofsky, MD, PhD, Kenneth Stein, MD, Gioia Turitto, MD, PhD, Stephen Winters, MD, M2Risk Investigators. University of Rochester, Cardiology Unit, Rochester, NY, Duke University Medical Center, Durham, NC, MetroHealth System, Cleveland, OH, Valley Health System, Ridgewood, NJ, University of Pennsylvania, Cardiology Unit, Philadephia, PA, SUNY-Stony Brook Health Sciences Center, Stony Brook, NY, UMassMemorial Medical Center, Worcester, MA, University of Maryland Medical Center, Baltimore, MD, Boston Scientific, Arden Hills, MN, New York Methodist Hospital, Brooklyn, NY, Electrophysiology Associates, Morristown, NJIntroduction: We conducted a comprehensive NIH-funded Multicenter ICD Risk Stratification Study (M2Risk Study) to determine which clinical and novel ECG-based variables will predict arrhythmic events and death in post-MI patients with EF≤35%.Methods: Post-MI patients with EF≤35% who received their ICDs for primary prevention of mortality were enrolled by 22 centers in the M2Risk Study. At enrollment, the following were collected: routine clinical data, 12-lead ECG, 24-hour

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MODERATOR BAND VT A SERIES OF PATIENTS AND OUR STRATEGY FOR SUCCESSFUL ABLATIONDaniel Benhayon, MD, Mathew Hutchinson, MD, Gregory Supple, MD, David Callans, MD, Sanjay Dixit, MD, Lidia Carballeira, MD, Erica Zado, PA, Maria Kohari, MD, Paban Saha, MD, Francis E. Marchlinski, MD and Fermin Garcia, MD. University of Pennsylvania, Philadelphia, PAIntroduction: The ablation of premature ventricular contractions (PVC) originating from the moderator band can pose significant anatomical challenges.Methods: We identified 6 out of 910 patients referred to our center since 2009 with VT or frequent PVCs that have been successfully mapped and ablated on the moderator band.Results: Three patients presented with PVC-induced polymorphic VT and ICD shocks, two with monomorphic VT and one with frequent PVCs. In all patients, the 12 lead ECG revealed VT or PVCs with a LB left superior axis (rS pattern in inferior leads) and a late precordial transition. The mean QRS duration was 148 ±16 ms. They all had a normal LV and RV function. All cases were done using intracardiac echo (ICE) to confirm anatomic localization and an electroanatomic mapping system to track activation and lesion deployment. In all, the RV bipolar and unipolar endocardial voltage was normal. The PVCs were localized to the moderator band and were eliminated with RF lesions that typically extended from the RV papillary muscle up to the septal insertion site of the moderator band (Fig). No complications were observed. All patients are arrhythmia free, off antiarrhythmic drugs after a median of 1 procedure (range 1-2) at a mean follow up of 16 months.Conclusion: Moderator band PVCs triggering polymorphic VF are commonly observed. They can be localized by a signature ECG pattern and successfully mapped and ablated. The use of ICE helps define the anatomic target and optimize likelihood of success.

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NOT ALL IRRIGATED CATHETERS TRANSFER HEAT SIMILARLY. A COMPARISON OF 4 OPEN-IRRIGATED CATHETERSCarolina Curiel, MEng, Javier Moreno, MD, PhD, María José Angulo, BSc, Jorge G. Quintanilla, MEng, Roberto Molina Morúa, MEng, María Jesús García Torrent, MSc, Carlos Macaya, MD, PhD and Julián Perez Villacastín, MD, PhD. Hospital Clínico San Carlos, Madrid, Spain, Universidad Rey Juan Carlos, Madrid, SpainIntroduction: There is great diversity of designs in open-irrigated ablation catheters (Cs). It is unknown whether they all


500ms received QT prolonging medications, which seemed to be associated with increased mortality. Patients taking ≥ 2 of these medications were at especially high risk. Increased awareness of QT prolonging multi pharmacy is needed.

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DELTAT50 AS A PROGNOSTIC MARKER IN AN ELDERLY POPULATIONChristina Abrahamsson, PhD, NIls Edvardsson, MD, PhD, Bo Skallefell, BSc, Leif Carlsson, PhD, Janeli Sarv, MSc, Lars Lind, MD, PhD and Göran Duker, PhD. AstraZeneca, Mölndal, Sweden, Sahlgrenska Academy, Göteborg, Sweden, Department of Medical Sciences, Uppsala, SwedenIntroduction: Repolarization instability, measured as increased beat-to-beat QT interval variability, has been documented in patients with cardiovascular disease, and may hypothetically be of prognostic importance. To test this hypothesis, repolarization instability was investigated in an elderly population by using the recently developed deltaT50 method, which measures the temporal variability at 50% of the T-wave down slope. br>Methods: DeltaT50 was measured on 5 minutes resting ECGs from 899 subjects aged 70 (participants in a general health-screening programme in Uppsala, Sweden, the Prospective Investigation of the Vasculature in Uppsala Seniors, PIVUS). The subjects were divided into three groups; CV-healthy who were alive at age 75 (N=116), subjects with any CV-diagnosis who were alive at age 75 (N=736) and subjects who were deceased at age 75 (N=47, all-cause mortality).Results: DeltaT50 was lower in the CV-healthy subjects (1.31 ±0.46 ms, mean±SD) than in the subjects with a CV-diagnosis (1.64±1.06 ms) and in the subjects who were deceased at age 75 (1.96±0.87 ms). DeltaT50 was >3 ms in 0.8 % of the CV-healthy, in 5 % of the subjects with a CV-diagnosis and in 12.8 % of the subjects who were deceased at age 75 and > 2.5 ms in 4.1, 10.5 and 27.7% of the subjects in the respective groups. Hence, deltaT50 was higher, and a larger proportion had outlying values, in the subjects with an inferior prognosis, i.e. those with a CV-diagnosis and those who died before age 75, than in the CV-healthy subjects. br>Conclusion: In this elderly population, deltaT50 correlated with the prognosis based on health status at age 70 and survival at age 75, which indicates that deltaT50 may be a variable of prognostic importance. br>

Holter monitoring (Mortara Instruments), signal-averaged ECG [SAECG] (Arrhythmia Research Technology), and exercise-induced T wave alternans [TWA] (Cambridge Heart). The prespecified ECG-based parameters included: heart rate variability, heart rate turbulence, deceleration capacity, ventricular arrhythmias on the 24-hour Holter, QRS duration, QRS complexity, QTc duration, T wave complexity, SAECG-derived: total QRS root mean square voltage (TRMS) and late potentials parameters (fQRSd, RMS, LAS), and TWA presence. Primary endpoints included: VT/VF requiring ICD therapy, death, and VT/VF or death.Results: There were 484 patients enrolled (17% females) aged 64±10 years who were followed for 27±18 months on average. VT/VF occurred in 49 (10.1%), death in 44 (9.1%), and VT/VF or death in 94 (19.4%) patients. None of clinical variables predicted VT/VF. VT/VF was predicted by frequent VPBs >500/24hours (HR=1.95; p<0.05), and by the TRMS<25µV from SAECG (HR=2.42; p<0.01). None of other ECG-based variables predicted VT/VF. BUN>25 mg/dl was the only clinical variable predictive for death (predominantly non-arrhythmic). Abnormal heart rate turbulence categorized as HRT2 (TS and TO abnormal) or as turbulence slope <2.5 RR/ms was independently associated with mortality (hazard ratios for HRT2=4.23; p=0.006, for HRT1 =2.30; p=0.133, and for TS<2.5 = 2.48; p=0.025). None of other variables was predictive for mortality after adjustment for clinical covariates.Conclusion: Arrhythmic events in postinfarction patients receiving ICDs are predicted by frequent VPBs on Holter and low QRS voltage on SAECG. Death in such ICD patients is predicted by elevated BUN and abnormal heart rate turbulence. Different clinical and ECG variables predict mortality and arrhythmic events.

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QT PROLONGING MEDICATIONS ARE FREQUENT IN PATIENTS WITH HIGH RISK OF MORTALITYKristina H. Haugaa, MD, PhD, J. M. Bos, MD, PhD, Robert F. Tarrell, MS, Bruce W. Morlan, MS, Pedro J. Caraballo, MD and Michael J. Ackerman, MD, PhD. Mayo Clinic, Rochester, MNIntroduction: QT prolonging medications are common and are used in all disciplines of medicine. We explored the frequency of exposure to QT prolonging medications, the types of QT prolonging medications used, and the mortality in patients with QTc > 500 ms.Methods: During 7 months, 86,107 ECGs were performed in 53,286 patients at the Mayo Clinic, MN. Of these, 1145 had QTc > 500 ms and were reviewed manually. ECGs with pacing, atrial fibrillation and bundle branch block were excluded. All QT prolonging medications within 7 days prior to the ECG were collected from the electronic medical records. QT prolonging medications were defined by presence on the Arizona CERT QT drug list.Results: In all, 470 (41%) patients exhibited a QTc ≥ 500 with no ECG exclusion criteria (55 ± 24 years, 56% female). A total of 530 QT prolonging medications were given to 309 patients with a median of 1 medication per patient (range, 0 - 5). Antidepressants were most common (30%), followed by antiarrhythmics (23%), and antibiotics (23%). Amiodarone was the most frequent single medication, followed by ondansetron. All-cause mortality during 224 ± 173 days of follow-up was 19% (87/470). Number of QT prolonging medication was an age and gender independent predictor of mortality (HR 1.24, 95% CI 1.06-1.44, p < 0.01). In patients who received ≥ 2 QT prolonging medications, mortality was markedly increased (36/134, 27% vs. 51/336, 15%, log rank p=0.005)(Figure).Conclusion: A considerable number of patients with QTc >


between the date of BNP measurement and the date of ICD implantation were excluded.Results: During a mean follow-up of 820+211 days, appropriate ICD therapies were delivered in 23.5% (38/162) of the patients; 30.2% (49/162) of the patients died. In multivariable Cox regression analysis, BNP values in the upper 50% for this cohort were the strongest predictor of appropriate ICD therapy after adjustment for sex, age, LVEF, NYHA class, history of CAD, amiodarone use, BUN, glomerular filtration rate, and atrial fibrillation (adjusted Hazard Ratio [HR] 5.75; 95% CI 2.0-16.5; p<0.001). Patients were divided into quartiles based on BNP levels. Estimated incidence of appropriate ICD therapy in patients in the lowest BNP quartile was 12%, compared with 17%, 62%, and 81% in the second, third, and highest quartile, respectively. The HR for appropriate ICD therapy of patients in the highest and second-highest quartiles of BNP values (adjusted HR 12.9, p<0.001 and HR 4.6, p=0.03, respectively) were higher than the HR for total mortality in these two quartiles (HR 3.4, p=0.021 and HR 2.3, p=NS, respectively).Conclusion: In this study, baseline BNP was a remarkable predictor of appropriate ICD therapy more than total mortality, independent of other risk factors. Use of BNP as a risk factor may lead to more cost-effective use of ICDs for primary prevention of sudden cardiac death.

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CONDUCTIVE CHANNELS IDENTIFIED BY CONTRAST-ENHANCED MAGNETIC RESONANCE IMAGING PREDICT VENTRICULAR TACHYARRHYTHMIA IN PATIENTS WITH SYSTOLIC HEART FAILURE RUNNING TITLE: CONDUCTIVE CHANNELS IN PATIENTS WITH HEART FAILURELian-Yu Lin, MD, PhD, Mao-Yuan Su, PhD, Jien-Jiun Chen, MD, Ling-Ping Lai, MD, PhD, Wen-Yih Tseng, MD, PhD and Jiunn-Lee Lin, MD, PhD. National Taiwan University Hospital, Taipei, TaiwanIntroduction: One recent study demonstrated that the CC (conductive channel) formed by heterogeneous tissue within the core scar could be detected by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) image and is responsible for clinical ventricular tachyarrhythmia. We hypothesized that the CC could help identify HF (heart failure) patients at risk for ventricular tahcyarrhythmia (VT).Methods: A total of 63 patients from our MRI database with left ventricular ejection fraction (LVEF) below 50% were included. The cine and LGE images were analyzed to derive the LV function, scar characteristics and to identify the CC. The outcomes, including VT and ventricular fibrillation (VF) and total mortality, were obtained by reviewing medical records.Results: After 1180.7±848.7 days of follow-up, 8 patients had VT/VF attack and 14 patients died. Among the MRI image parameters, LVEF was lower in patients with VT/VF (29.5±5.4 % vs. 35.0±9.4 %, P = 0.029) and the chance of the identification of the CC by LGE-CMR was higher in patients with VT/VF (75.0% vs. 16.4%, P < 0.001). The chance of the identification of the CC was also higher in total mortality (50.0 % vs. 16.3, P = 0.010). Other LGE-MRI variables were not different between the two groups. Cox’s regression model showed that only the identification of the CC was positively associated with VT/VF attack during follow-up (HR = 31.877, 1.830-554.254, P = 0.018). The region of the core scar (HR = 1.065, 1.017-1.115, P =0.007) and the identification of the CC (HR = 4.696, 1.084-20.350, P =0.039) were predictors for excess total mortality.Conclusion: We demonstrated that the CC identified in LGE-CMR image can help identify HF patients at risk of ventricular tachyarrhythmia.

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SEVERE CARDIAC AUTONOMIC FAILURE AS A PREDICTOR OF MORTALITY IN AORTIC VALVE STENOSIS: PREDICT-ASAxel Bauer, MD, Christine S. Zürn, MD, Konstantinos D. Rizas, MD, Christian Eick, MD, Marie-Isabel Vogtt, Cosmina Stoleriu, MD and Meinrad Gawaz, MD. Eberhard-Karls-Universität Tübingen, Tübingen, GermanyIntroduction: Patients with aortic valve stenosis (AS) are exposed to an increased risk of mortality including sudden cardiac death. Current risk stratification concepts are based on assessment of the patient’s symptomatic status and echocardiographic markers but suffer from important limitations. In this prospective cohort study, we tested whether presence of severe cardiac autonomic failure (SAF) is an important prognostic marker in patients with AS.Methods: We prospectively enrolled consecutive patients who presented for evaluation of AS at our institution. Patients were included if aortic valve area was ≤1.5 cm2 or mean aortic gradient was ≥25 mmHg and if they presented in sinus rhythm. SAF was defined as coincidence of abnormal autonomic reflex function (assessed via heart rate turbulence) and abnormal autonomic tonic activity (assessed via heart rate deceleration capacity). The primary endpoint was all-cause mortality within the first 2 years of follow-up. Multivariable analyses considered SAF and conventional risk predictors: presence of symptoms, impaired left ventricular ejection fraction (LVEF) ≤50%, increased levels of brain natriuretic peptides (BNP), and renal insufficiency.Results: Of the 510 patients screened, 323 patients fulfilled the inclusion criteria. During follow-up, 42 patients died. The estimated 2-year mortality rate was 43.2% among 66 SAF-positive patients vs. 9.7% among SAF-negative patients (P<0.0001). Multivariable analysis identified SAF as the strongest independent predictor of mortality (hazard ratio [HR] 3.0; 95% confidence interval [CI], 1.6 to 5.8; P<0.001). SAF was a particularly strong predictor of mortality in asymptomatic patients (HR 6.7; 95% CI, 2.0 to 21.9; P=0.002) and patients with preserved LVEF (HR 9.0; 95% CI, 3.8 to 21.0; P<0.001) or normal BNP levels (RR 7.1; 95% CI, 2.9 to 17.1; P<0.001).Conclusion: SAF identifies a high-risk group among patients with AS who have a poor prognosis and are not identified by conventional risk predictors. Future studies are needed to test whether SAF-guided therapy in patients with AS improves outcome.

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N-TERMINAL PRO-B-TYPE NATRIURETIC PEPTIDE IS A MAJOR PREDICTOR OF APPROPRIATE ICD THERAPYYehoshua C. Levine, MD, Murray Mittleman, MD, Michael Rosenberg, MD and Alfred E. Buxton, MD. Beth Israel Deaconess Medical Center, Boston, MAIntroduction: Effective use of ICDs for prevention of sudden cardiac death requires use of risk factors that are associated with arrhythmias, not just total mortality. Few risk factors exist for which arrhythmic risk exceeds total mortality risk. N-terminal pro-B-type natriuretic peptide (BNP) has been associated with ventricular arrhythmias (VA) in patients with ICDs, but it is not clear whether this relationship is independent of other risk factors and/or is secondary to increased total mortality risk. We sought to determine whether BNP is an independent predictor of VA in ICD patients.Methods: 162 patients with BNP values available within 9 months of initial ICD implantation were retrospectively assessed for occurrence of first episode of appropriate ICD therapy (antitachycardia pacing or shocks for VA). Patients with cardiogenic shock or heart failure-related hospitalizations


by identification of the morphologic right atrium, utilizing the respective AV valve locations and coronary sinus (CS) if present. Ablations (Radiofrequency or Cryo energy) were performed in the lower 3rd of KT with occasional advancement towards the middle or upper 3rd of the KT for select cases.Results: Thirty three pts [19 F/14 M]; mean age 17 (range 2-53) years and mean weight 48 (range 13-120) kg were included. Diagnoses included single ventricle (SV) in 13 (5/13 with heterotaxy); D-loop transposition of the great arteries (TGA) in 4; physiologically corrected TGA in 2; venous anomalies in 4; Ebstein anomaly in 3; tetralogy of Fallot in 2 and other in 5. The AVNRT was typical in 21, atypical in 9 and both in 3. Ablation was attempted in 30/33 (91%) pts, using radiofrequency energy in 18, cryoablation in 6 and both in 6. Ablation approach was antegrade in 18/30 (60%), trans-baffle in 9/30 (30%) and retrograde in 3/30 (10%). Acute success rate was 93 % (28/30). Additional arrhythmias were present in 14/33 (44%) (intra-atrial reentrant tachycardia, accessory pathway mediated supraventricular tachycardia, ventricular tachycardia). One complex Fontan patient had permanent PR prolongation suggesting inadvertent fast pathway damage from cryo energy, but no patient had high-grade AV block. At a mean follow-up of 22 months, only one recurrence of AVNRT was documented in the 22 of 30 pts.Conclusion: AVNRT can occur in CHD, and is frequently associated with other arrhythmias. Individualized approaches and delineation of the KT with understanding of the anatomy can yield good results and low complication rates with catheter ablation.

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DOES PEDIATRIC CRT INCREASE THE RISK OF VENTRICULAR TACHYCARDIA?Jennifer L. Perera, MD, Kara S. Motonaga, MD, Christina Y. Miyake, MD, Kishor Avasarala, MD, Rajesh Punn, MD, Elif S. Selamet Tierney, MD, David N. Rosenthal, MD and Anne M. Dubin, MD, FHRS. Stanford University, Palo Alto, CA, Children’s Hospital and Research Center, Oakland, CAIntroduction: Long term outcome data in cardiac resynchronization therapy (CRT) in pediatric patients is lacking. We aimed to describe the long term outcomes in this diverse patient population.Methods: We performed a retrospective chart review of pediatric patients with CRT between May 2003 and July 2012, with a mean follow up of 2.75 ± 2.53 years. Baseline patient characteristics including patient clinical status, electrocardiogram, and echo measures were compared to most recent follow-up data. Survival and complications were gathered.Results: 67 patients (57% male) received CRT therapy. Seven patients (10.4%) had congenital complete heart block, 50 patients (74.6%) had congenital heart disease (CHD), and 10 patients (14.9 %) had dilated cardiomyopathy; 41 patients with CHD also had complete heart block. In long term follow up, ejection fraction increased from 43.8 +/- 17.6 % to 53.8 +/- 13.4 (p=0.03), and QRS duration decreased (146 ± 33ms to 119 ±17ms, p < 0.01). Ventricular end-diastolic volume improved, decreasing from 83.2 +/- 48.8 mL to 44.4 +/- 20.7, p <0.001. Patients had a median of one hospital readmission (range 0-7), most commonly for generator change. There were no procedural deaths, however there were 5 late deaths (7.5%); 3 secondary to pump failure and 2 sudden deaths. One additional patient was successfully resuscitated from a sudden cardiac arrest. The incidence of ventricular tachycardia (VT) increased after CRT (10% v 25% p=0.02). There were no observed differences in rates of supraventricular tachycardias.Conclusion: Despite decreased QRS duration, improved

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CARDIAC SARCOIDOSIS MASQUERADING AS ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA/CARDIOMYOPATHY: EXPERIENCES FROM THE JOHNS HOPKINS ARVD/C REGISTRYBinu Philips, MD, Srinivasa Madhavan, MD, Cynthia James, PhD, Crystal Tichnell, MS, Brittney Murray, MS, Saman Nazarian, MD, PhD, Hugh Calkins, MD, Harikrishna Tandri, MD and Alan Cheng, MD. Johns Hopkins Hospital, Baltimore, MDIntroduction: Patients with cardiac sarcoidosis (CS) are often difficult to distinguish from those with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and this results in delay of proper management. We sought to identify clinical features which can aid in differentiating these disease states.Methods: The study population compromised 15 patients with cardiac sarcoidosis who were initially misdiagnosed as ARVD/C and 30 patients with definite ARVD/C by the Revised Task Force Criteria. The clinical, electrocardiographic, electrophysiologic, and imaging features were compared between the two groups.Results: Among the 15 patients misdiagnosed as ARVD/C, 7 (47%), 6 (40%), and 2 (13%) fulfilled the revised Task Force criteria for definite, borderline, and probable ARVD/C, respectively. Cardiac sarcoidosis was eventually diagnosed by myocardial biopsy in 7 (47%) patients. Pulmonary, conjuctival, and skin biopsies confirmed the diagnosis in the remaining 8 patients. The mean age at presentation was 24.8 and 43.9 years for patients with definite ARVD/C and CS, respectively. Frequent ventricular ectopy (>1000 PVC/24 hours) was present more commonly in ARVD/C patients (28 (93%) vs 8(53%); p=0.0034). 12-lead ECG showed prolonged PR intervals (157.6 vs 215.1 ms; p <0.0001) and QRS intervals (95.9 vs 132.4 ms; p=0.0002) among the CS group. Second and third degree AV block was present in 7 (47%) patients with CS and no patient with ARVD/C (p<0.0001). During electrophysiologic testing, the HV interval was prolonged in CS as compared to the ARVD/C cohort (42.9 vs 63.8; p<0.0001). The mean number of VT induced was 1.5 vs 2.8 (p=0.007) in the ARVD and CS groups, respectively. Imaging studies showed septal scar in 7 (47%) CS patients while patients with ARVD/C had perivalvular scar without septal involvement.Conclusion: ARVD/C patients present earlier with symptoms and have frequent ventricular ectopy. Electrocardiographic and electrophysiologic abnormalities including prolonged intervals and second/third degree AV block were commonly seen in CS patients. Finally, imaging studies commonly showed septal involvement with CS. Taken together, these characteristics can be helpful in distinguishing the two overlapping disease entities.

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CATHETER ABLATION OF AV NODE RE-ENTRANT TACHYCARDIA IN CONGENITAL HEART DISEASEShailendra Upadhyay, MD, Anne Marie Valente, MD, John Triedman, MD, Frank Cecchin, MD and Edward P. Walsh, MD. Boston Children’s - Brigham & Women’s Hospital, Boston, MA, Boston Children’s Hospital, Boston, MAIntroduction: Congenital heart disease (CHD) pts may have variable locations of AV Node (AVN) as a consequence of the underlying anatomy or surgical repairs which makes slow pathway modification of AVN for treatment of AVN re-entrant tachycardia (AVNRT) challenging. The safety and efficacy for catheter ablation of AVNRT in CHD is not well known.Methods: We performed a retrospective review of CHD pts who underwent an invasive electrophysiology study from 2001 to 2012, with a diagnosis of AVNRT. Ablation of AVNRT involved approximate delineation of the Koch’s triangle (KT)


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REMOTE MONITORING OF CARDIOVASCULAR IMPLANTABLE DEVICES IN THE PEDAITRIC POPULATION IMPROVES DETECTION OF ADVERSE EVENTSLindsey E. Malloy, DO, Jean Gingerich, BSN and Dianne Atkins, MD, FHRS. University of Iowa, Iowa City, IAIntroduction: With the exponential growth of cardiovascular implantable electronic devices (CIEDs) in pediatric patients, a new method of long term surveillance, remote monitoring (RM), has been developed. The purpose of this study was to determine the usefulness of RM as a monitoring tool in the pediatric population. We hypothesized that remote monitoring shortened the duration of detection of adverse events prompting earlier corrective measures.Methods: A retrospective review was performed of 162 patients at the University of Iowa Children’s Hospital who had an implantable cardiac device. Data transmitted by a remote home monitoring system were analyzed. Patient demographics, mean interval between remote transmissions, detection of adverse events requiring corrective measures including detection of lead failure in those patients with recalled leads, detection of arrhythmias and device malfunctions independent of symptoms, average time gained in the detection of events using remote monitoring versus standard practice, sensitivity and specificity of remote monitoring, and the impact of remote monitoring on data management was examined.Results: The median time between remote transmissions was 93 days (range 1-842 days). Of the 615 total transmissions, 16% had detected adverse events, 11% prompting clinical intervention. One patient was found to have lead failure on RM included in the lead recall before an inappropriate shock was delivered. Of those with events requiring clinical response, 61% of patients reported symptoms while 39% had no reported symptoms. The median interval between last follow-up and occurrence of events detected by remote monitoring was 46 days (range 1-467 days), representing a temporal gain of 134 days for patients followed at 6 month intervals and 44 days for patients followed at 3 month intervals. The sensitivity of remote monitoring was found to be 99% while the specificity was found to be 72%. In 2011, there was a mean of 0.6 remote transmissions a day, equating to approximately 4 transmissions a week.Conclusion: Remote monitoring allows early identification of arrhythmias and device malfunctions prompting earlier corrective measures, which improves the care and safety of pediatric patients.

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SAFETY OF SPORTS FOR PEDIATRIC AND CONGENITAL ICD AND PACEMAKER PATIENTSElizabeth V. Saarel, MD, Thomas A. Pilcher, MD and Susan P. Etheridge, MD. University of Utah, Salt Lake City, UTIntroduction: The safety of sports participation for children and congenital heart patients with pacemakers (PMs) and implantable cardioverter defibrillators (ICDs) is unknown, and recommendations among physicians may vary widely. The purposes of this study were to determine current practice among patients with PMs or ICDs and their physicians regarding sports participation, and to determine how many physicians have cared for patients who have sustained adverse events during sports participation.Methods: A survey was emailed to all 280 members of the international Pediatric and Congenital Electrophysiology Society.Results: Among 111 physician respondents, recommendations

ventricular function and reduced ventricular volumes, VT burden increased following CRT. This finding raises the question of increased arrhythmogenicity following CRT therapy in the pediatric population, and warrants further investigation.

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DO IMPLANTATION GUIDELINES PREDICT APPROPRIATE DEFIBRILLATOR THERAPY IN CHILDREN?Christopher Ratnasamy, MD, Orhan Cilinc, MD, Christopher Swearingen, PhD and Jeffrey Gossett, MS. Arkansas Childrens Hospital, Little Rock, ARIntroduction: We hypothesized that meeting ACC/AHA guidelines for defibrillator implantation in hypertrophic cardiomyopathy (HCM) and long QT syndrome (LQTS) will predict appropriate defibrillator therapy (ADT) in children.Methods: HCM and LQTS patients who received a defibrillator < 18 y of age between 1999 and 2011 at Arkansas Children’s Hospital were reviewed. Association between ADT and indication for implant (Class 1 and 2A vs others) as well as the association between adverse events with age at implant (<10 vs >=10 y) were estimated.Results: 16 HCM and 39 LQTS (55 total) patients met study criteria and were included in analysis. Patient’s meeting Class 1 and 2A guidelines at implantation were more likely to have ADT (33% vs 4%, p=0.007). All ADT are shown in Figure. Median follow up was 34 and 46 months respectively. Patient’s age <10 years at the time of ICD implantation was significantly associated with adverse events as summarized in Table 1.Conclusion: Current guidelines for HCM and LQTS predict ADT in children.

Table 1. Adverse Events by Age Group

Age < 10 years(n=15)

Age ≥10 years (n=40) P-value

Age of Implant (years)* 7.1 (2.1, 7.9) 15.2 (13.1, 16.7)

Epicardial 67% (10) 0% (0)

Need for additional surgical intervention 53% (8) 18% (7) 0.008

Lead Fracture 40% (6) 5% (2) 0.003

Local Infection 7%(1) 2% (1) 0.475

Pocket Revision 7% (1) 2% (1) 0.475

Inappropriate shocks 7% (1) 10% (4) 0.999

T-Wave Oversensing 0% (0) 12% (5) 0.308

Follow Up (months)* 48.0 (36.0, 61.0) 36.0 (23.0, 53.0) 0.2†

*Median (Interquantile range) and †Wilcoxon rank Sum reported. Otherwise, %(N) and Fisher’s Exact reported.


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PREVALENCE AND MORPHOLOGICAL PROPERTIES OF ANATOMICAL ISTHMUSES INVOLVED IN MONOMORPHIC VENTRICULAR TACHYCARDIA IN REPAIRED TETRALOGY OF FALLOTGijsbert F. Kapel, MD, Sergio Laranjo, MD, Katja Zeppenfeld, MD, PhD, Nico A. Blom, MD, PhD, Martin J. Schalij, MD, PhD, Monica R. Jongbloed, MD, PhD and Margo M. Bartelings, PhD. Leiden University Medical Center, Leiden, Netherlands, Hospital de Santa Marta, Lisabon, PortugalIntroduction: Ventricular tachycardia (VT) is an important cause of late morbidity and mortality in repaired Tetralogy of Fallot (rTOF). The majority of VTs in rTOF are monomorphic VTs due to macro-re-entry using well defined anatomical isthmuses that can be successfully targeted with radiofrequent catheter ablation (RFCA) in most patients. The prevalence and properties of these isthmuses in the rTOF population are unknown. Extending this knowledge might facilitate RFCA of VT in rTOF.Methods: In 28 post-mortem specimens with rTOF (age 80±65 months) the presence and width of anatomical isthmuses were assessed. Isthmuses were defined as (1) the isthmus between tricuspid annulus (TA) and RV-scar or RVOT-patch, (2) the isthmus between RV-scar and pulmonary annulus (PA), (3) the isthmus between PA and VSD-patch and (4) the isthmus between VSD-patch and TA. Furthermore, presence of coronary arteries abnormalities, thickness between isthmus 3 and the aortic root and the degree of infundibular resection were assessed.Results: Total correction with a transannular patch was performed in 75% (n=21) of hearts; the remaining had RV myectomy with direct closure of the RV. Isthmus 1 (width 23±9 mm) and isthmus 3 (width 13±6) were present in all rTOF specimens. Isthmus 2 (width 7±5 mm) and isthmus 4 (width 6±4 mm) were present in respectively 21% (n=6) and 11% (n=3) of hearts. No major coronary artery abnormalities were found; in 11% of cases a large conal branch, anterior to isthmus 1, was present. The area between isthmus 3 and the aortic root had an average thickness of 7±2mm, independent of age. Infundibular resection was performed in 93% (n=26) of specimens, which was mild to moderate in 39% and severe to extreme in 54% of cases.Conclusion: Isthmus 1 and 3 were present in all rTOF specimens. The distance between isthmus 3 and the aortic root, as well as the normal coronary artery pattern of most specimens would allow to perform safely RFCA and possibly reach transmurality. Infundibular muscle resection was severe to extreme in 54% of the rTOF specimens, which might result in significant scarring of isthmus 3.

varied widely. Physicians recommended avoidance of all sports more vigorous than golf for only 3% of patients with PMs and 14% of patients with ICDs. For PMs 61% recommended avoidance of contact, and 4% recommended avoidance of competitive sports. For ICDs 30% recommended avoidance of contact, and 15% recommend avoidance of competitive sports. Most classify middle school travel and high school teams as competitive in contrast to recreational sports in middle and elementary school. Ninety six percent based restrictions on patients’ underlying heart disease. Physicians cited physical (96%) and mental (97%) health benefits as reasons for allowing sports participation in their patients with PMs or ICDs. Regardless of recommendations, most physicians reported caring for patients who participated in sports, including many citing vigorous and competitive sports. ICD therapies during sports were common, with appropriate shocks cited by 60% and inappropriate shocks cited by 55% of physicians. Adverse consequences during sports were described. Twenty percent of physicians reported a known injury to a PM patient and 7% reported a known injury to an ICD patient during sports. Medical-legal concerns impact sports participations recommendations in 91% of physicians.Conclusion: Physician recommendations for sports participation in pediatric and congenital patients with PMs or ICDs varies widely. Many patients with PMs or ICDs do participate in vigorous and even competitive sports. ICD shocks are common.

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THE PATHOLOGIC SUBSTRATE OF VENTRICULAR TACHYCARDIA IN TETRALOGY OF FALLOTAtsuko Seki, MD, Jeremy P. Moore, MD, Kevin M. Shannon, MD and Michael C. Fishbein, MD. UCLA Medical Center, Department of Pathology, Los Angeles, CA, UCLA Medical Center, Department of Pediatrics, Los Angeles, CAIntroduction: Ventricular tachycardia (VT) is a major cause of morbidity and mortality for patients with tetralogy of Fallot (TOF). Catheter ablation can be used to interrupt the critical isthmus of the reentrant VT circuit, but there is limited knowledge regarding the natural and surgical variations in isthmus pathology.Methods: All autopsy hearts at the UCLA Medical Center with the diagnosis of TOF were examined by either gross or histological method. Isthmuses were classified as 1A) ventriculotomy (V)-to-tricuspid annlulus (TA), 1B) V-to-VSD patch, 2) V-to-pulmonary valve (PV), 3) PV-to-VSD patch, and 4) VSD patch-to-TA. Length and thickness were measured and normalized to LV length. Substrates were examined by light microscopy when not discernible by gross inspection.Results: Forty-three hearts with TOF were examined, 27 of which had undergone previous intracardiac repair and were included. Isthmus 1A and 1B were both present in 25 (93%), isthmus 2 in 6 (22%), isthmus 3 in 24 (89%), and isthmus 4 in 5 (19%). With the exception of isthmus 2 length, the mean normalized isthmus length and thickness were both greatest for group 1A relative to other isthmuses (p<0 001), including the previously undescribed isthmus 1B (Figure). For subjects ≥ 8 yrs (n=13), mean absolute isthmus 1A length was 3.7 cm, 1B was 2.8 cm, 2 was 2.9 cm, 3 was 1.4 cm, and isthmus 4 was 0.2 cm. Isthmus 4 was found in only 1 specimen >8 yrs.Conclusion: Consistent isthmus characteristics are found among patients with repaired TOF. Isthmus 1A has the least favorable characteristics for catheter ablation, whereas isthmuses 2 and 4 were more favorable but uncommon. Isthmus number 3 is both common and associated with dimensions suitable for catheter ablation.


Methods: We created two patient centered educational videos (one with white participants and one with black participants) that included visual animation, physician commentary and patient testimonials, on sudden cardiac arrest (SCA) and ICD therapy. The primary study outcome was the decision to receive an ICD as a function of race and intervention. Secondary outcomes included decisional conflict, improvement in patient knowledge of ICD therapy, and receipt of an ICD within 90 days. Between January 1, 2011 and December 31, 2011, 59 patients (37 white and 22 black) eligible for a primary prevention ICD were randomized to the video or usual care (UC).Results: Relative to white patients, Black patients were younger (median age 55 vs. 68 years) and more likely to have attended college or technical school. Baseline SCA and ICD knowledge was similar and this knowledge improved significantly in both racial groups after the intervention. Black patients were less likely than white patients to want an ICD in both the video and UC arms (54.5% vs. 81.1%, p=0.03) and (84.6% vs. 42.9%, p=0.052) respectively. Blacks were less likely than whites to receive an ICD at 90 days (89.2% vs. 63.6%, p=0.052). Decisional conflict was similar among black and white patients who watched the video compared with those who did not.Conclusion: Among individuals eligible for a primary prevention ICD, black patients were less likely than white patients to want an ICD. While a decisions support video tool increased patient knowledge, it did not reduce racial differences in patient preference for an ICD, conflict associated with the decision, or rates of actually receiving an ICD.

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USE OF THE INTERNET AS A PRIMARY SOURCE OF HEALTHCARE INFORMATION IS NOT AFFECTED BY DEMOGRAPHIC VARIABLESSeena Monjazeb, Amirreza Solhpour, MD, James T. Willerson, MD, Patrick Cook, MD, Roberto Lufschanowksi, MD, George Younis, MD, William E. Cohn, MD, James J. Livesay, MD and Mehdi Razavi, MD. University of Texas at Austin, Austin, TX, Texas Heart Institute at St. Luke’s Episcopal Hospital, Houston, TXIntroduction: Because healthcare is closely tied to socioeconomic status (SES), there is a gap in the healthcare received by persons with low SES. The Internet a potentially important source of healthcare information is thought to be used mainly by high-SES individuals. To allow the public to ask questions anonymously and receive a physician response, we created an Internet portal called Ask a Texas Heart Institute Doctor (AATHID). The site has received questions from persons in 50 states and 82 foreign countries. To compare the characteristics of persons who use and do not use the Internet as their primary source of medical information, we assessed traits of individuals who voluntarily completed AATHID’s demographic form.Methods: We used Student’s t test to compare the ages of participants and the χ2 test to compare binary categorical variables.Results: From January 2010 to May 2012, 526 persons (289 women and 237 men) completed AATHID’s demographic form: 89% said they would be willing to communicate with their doctor via email and share their medical records, and 56% said they use the Internet versus conventional sources as their main source of healthcare information (see Table).Conclusion: Demographic traits are similar among persons who use and do not use the Internet as their primary source of medical information. Both groups have features of under-served populations. Unemployed status and lower educational level do not predict Internet non-use. Indeed, the Internet is widely used by low-SES individuals for healthcare information.

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COST-UTILITY ANALYSIS OF REMOTE MONITORING IN HEART FAILURE PATIENTS WITH IMPLANTABLE DEFIBRILLATORS: RESULTS FROM THE EVOLVO STUDYMaurizio E. Landolina, Sr., MD, Giovanni B. Perego, MD, Paolo Zanaboni, MD, Maurizio Marzegalli, MD, Maurizio Lunati, MD, Giuseppe Guenzati, MD, Antonio Curnis, MD, Silvia Bisetti, MS, Francesca Borghetti, MS, Gabriella Borghi, MS and Cristina Masella, MS. Policlinico San Matteo, Pavia, Italy, Istituto Auxologico S. Luca Hospital, Milano, Italy, Norwegian Centre for Integrated Care and Telemedicine, University Hospital of North Norway, Tromsø, Norway, S. Carlo Borromeo Hospital, Milan, Italy, Niguarda Ca’ Granda Hospital, Milan, Italy, Spedali Civili, Bescia, Italy, Medtronic Italia, Milan, Italy, CEFRIEL - Regione Lombardia, Milan, Italy, Department of Management, Economics and Industrial Engineering, Politecnico di Milano, Milan, ItalyIntroduction: Heart failure (HF) patients with implantable defibrillators (ICD) place a significant burden on health care systems. We hypothesized that remote device monitoring represents a cost-effective approach. This paper summarizes the economic results of the EVOLVO clinical trial that evaluated disease management of HF patients implanted with ICD.Methods: 200 patients (79% males; 66±10years) implanted with ICD (92% biventricular ICD) were randomized to remote versus standard control, with a follow-up of 16 months. The economic evaluation included analyses with the perspectives of the main stakeholders and cost-utility. Cost-utility was performed for 180 patients for whom QALYs were available.Results: The rate of cardiac or device related unplanned emergency department (ED) or urgent in-office visits was reduced by 36% in remote arm (75 versus 117; Incidence density: 0.59 versus 0.93 events/year; p=0.005). Overall, there were 1285 healthcare utilizations (secondary endpoint) with a difference of 23% in the rates of events (4.40 events/year in remote arm vs 5.74 events/year in standard arm). Overall, the remote control showed annual cost savings for the health care system (€1962.78 versus €2130.01; p=0.804), although not significant. There was also a significant reduction of the annual cost for the patients in the remote arm in comparison to the standard arm (€291.36 versus €381.34; p=0.015), while an increase in the annual workload per patient emerged for the health professionals. The patients in the remote arm gained 0.065 QALYs more than those in the standard arm over 16 months, with a cost savings of €888.10 per patient.Conclusion: Remote management of HF patients with ICD appears to be a cost-effective solution over the standard method of in-office evaluations, with clinical and economic benefits for both health care systems and patients. A large-scale adoption should be supported by adequate organisational measures.

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EDUCATIONAL VIDEOS TO REDUCE RACIAL DISPARITIES IN ICD THERAPY VIA INNOVATIVE DESIGNS (VIVID): A RANDOMIZED CLINICAL TRIALKevin L. Thomas, MD, Louise Zimmer, MPH, MA, David Dai, MS, Sana M. Al-Khatib, MD and Eric Peterson, MD, MPH. Duke Clinical Research Institute, Durham, NCIntroduction: Blacks eligible for an implantable cardioverter defibrillator (ICD) are much less likely than whites to receive one. This disparity may in part be due to racial differences in patient preferences. We hypothesized that a targeted patient centered educational video decision support tool could reduce differences in ICD preferences and implantation rates.


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SEPARATION OF ICD HEADER FROM THE CAN MANIFESTING AS ATRIAL LEAD MALFUNCTIONArash Aryana, MD, P. Gearoid O’Neill, MD, Jason Schroeder, MBA, Arvin Arthur, MD and Kenny K. Charn, MD. Regional Cardiology Associates and Mercy Heart & Vascular Institute, Sacramento, CA, Boston Scientific Corporation, St. Paul, MN, Mercy Heart & Vascular Institute, Sacramento, CA, Regional Cardiology Associates and Mercy Heart & Vascular Institute, Jackson, CAIntroduction: We report a case of a weakened ICD header bond resulting in gross detachment from the can, posing as an atrial lead abnormality.Methods: N/AResults: A 76-year-old man received a dual-chamber ICD in 2003 for sustained VT, with subsequent replacement of the generator with a Boston Scientific TELIGEN ICD in 2010. He also had a history of CAD, CHF with preserved LV function, paroxysmal AF and tachy-brady syndrome. A routine ICD interrogation 18 months following replacement showed abnormal atrial lead findings, including intermittent loss of pacing capture at maximum output and elevated lead impedance > 2,000 ohms. However, P-wave sensing was generally stable without EGM artifact (Figure). All other parameters were normal without apparent generator or defibrillator lead malfunction (R-waves > 25.0 mV, pacing threshold: 0.7 V @ 0.5 ms, pacing impedance: 876 ohms, shock impedance: 48 ohms). In view of the patient’s need for atrial pacing, he was referred for atrial lead replacement. However, preliminary intraprocedural inspection of the ICD header revealed clear separation from the can (Figure). Further examination of the atrial lead showed no gross abnormalities with normal sensing, impedance and pacing threshold as confirmed through the analyzer.Conclusion: In patients with TELIGEN ICD, gross header/can separation as a result of weakened ICD header bond, can present as isolated atrial lead abnormality. This rare but unusual complication should be considered in patients with Boston Scientific TELIGEN ICD and COGNIS CRT devices that fall under this advisory.

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SPONTANEOUS DISSOCIATION OF RIGHT ATRIUM DURING ATRIOVENTRICULAR REENTRANT TACHYCARDIA USING A LEFT-SIDED BYPASS TRACTFarshad Raissi Shabari, MD, MPH, Alireza Nazeri, MD, Joanna Molina, MD, Mohammad Saeed, MD and Mehdi Razavi, MD. Texas Heart Institute, Houston, TXIntroduction: It has been previously reported that right atrial (RA) pacing can dissociate RA electrograms from the rest of heart during atrioventricular reciprocating tachycardia.Methods: N/AResults: A 25 year-old man presented with 7-year history of intermittent palpitations with a recent progression in frequency of his episodes. An electrocardiogram during an episode showed a wide complex tachycardia of 200 bpm. His echocardiogram was normal He underwent a standard 4 catheter electrophysiologic study. The baseline intervals were normal. Incremental atrial pacing reproducibly induced a regular, narrow complex tachycardia (CL 275 ms). Eight seconds after initial induction of the SVT, the RA recording showed a regular tachycardia (CL 196 ms) dissociated from the atrial recordings of CS, His, and ventricles (Figure 1). The latter 3 continued at the same rate as the original tachycardia. These two tachycardias ultimately degenerated to atrial fibrillation that in turn changed to a transient right-sided flutter which terminated spontaneously. There was no evidence of dual AV nodal pathways. The ventricular extrastimuli also induced the tachycardia. The earliest retrograde atrial activation was 1-2 cm within the coronary sinus (CS). A His-refractory PVC advanced atrial activation without change in activation pattern. The tachycardia proved to be an ORT using a posteroseptal accessory pathway. The AP was ablated through a retrograde approach.Conclusion: To the best of our knowledge this is the first report of spontaneous simultaneous combination of the two tachycardias in the atria. Although this dual tachycardia was not stable, it may play a role in genesis of atrial fibrillation in this patient.


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EPILEPTIC ASYSTOLEAbdurrahman Hamadah, MD, Megan Dulohery, MD, Yong-Mei Cha, MD and Malcolm R. Bell, MD. Mayo Clinic, Rochester, MNIntroduction: Cardiogenic syncopal episodes in patients with a known seizure disorder maybe overlooked as a normal part of their seizure disorder. These syncopal episodes may be a manifestation of asystole that is induced by seizure activity. The recognition and management of this phenomenon is of extreme importance.Methods: N/AResults: A 20-year-old woman with a four-year history of epilepsy, presented to our institution for workup of recurrent seizures despite appropriate anti-epileptic therapy. She had frequent episodes of convulsive seizures, but additionally noted history of drop attacks with no premonitory symptoms. Other than the medically treated epilepsy, she was healthy with a negative review of systems and physical exam. She was initially admitted to the epilepsy monitoring unit for continuous electroencephalogram (EEG). During the recording, she was noted to have an episode of sinus pause for 16 seconds associated with syncope. This episode recurred and was associated with brief convulsive activity. She underwent permanent single chamber (atrial) pacemaker implantation. Further monitoring on EEG demonstrated evidence of frontotemporal lobe seizure activity during which atrial paced rhythm was observed, without development of syncopal symptoms.Conclusion: Patients with history of seizure activity who are on appropriate anti-epileptic therapy and continues with syncopal episodes should be evaluated for arrhythmias including episodes of asystole. Temporal lobe epilepsy has been associated with ictal asystole and sudden death, a recognized potential cause of Sudden Unexpected Death in Epilepsy. Pacemaker implantation prevents asystole and syncopal symptoms. It is important to consider arrhythmias in the evaluation of seizure patients with a history of syncope.

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EEG NEGATIVE CARDIO-INHIBITORY SYNCOPE EFFECTIVELY SUPPRESSED WITH ANTIEPILEPTIC THERAPYAlex Y. H. Tan, MD, Yonathan Melman, MD, PhD, Susan Herman, MD, Kaarkuzhali B. Krishnamurthy, MD and Peter Zimetbaum, MD. Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, Beth Israel Deaconess Medical Center, Boston, MA, Division of Neurology, Beth Israel Deaconess Medical Center, Boston, MAIntroduction: Cardio-inhibitory syncope triggered by seizures is increasingly recognized and is diagnosed by EEG evidence of seizure activity preceding asystole. We however, present a case of recurrent EEG-negative cardio-inhibitory syncope treated effectively with anti-epileptic therapy.Results: The patient is a 31-year-old man with mild cerebral palsy and recurrent syncope since age 14. His typical events begin with a premonition or sense of warmth followed by loss of consciousness for 10 to 30 seconds and no obvious tonic-clonic movements. Brain MRI, EEG, cardiac event monitor and echo are normal. He was admitted to the hospital after suffering 3 episodes over 2 days. Continuous ECG and EEG monitoring was performed. Five syncopal episodes with 20-30 secs of asystole occurred in the first two days of monitoring. In each instance heart rate slowing and asystole was preceded

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ATRIAL POTENTIAL IN THE DISTAL GREAT CARDIAC VEIN AND ANTERIOR INTER-VENTRICULAR VEIN AS A GUIDE OF MAPPING AND ABLATION OF FOCAL ATRIAL TACHYCARDIA ORIGINATING FROM THE LEFT ATRIAL APPENDAGEItsuro Morishima, MD, Takahito Sone, MD, Hideyuki Tsuboi, MD, Michitaka Uesugi, MD, Etsushi Matsushita, MD, Yasuhiro Morita, MD, Yasunori Kanzaki, MD and Toshiro Tomomatsu, MD. Ogaki Municipal Hospital, Ogaki, JapanIntroduction: The ventricular potentials in the distal great cardiac vein and the anterior inter-ventricular vein (GCV-AIV) have gaining increasing interests as they relate to the radiofrequency ablation (RFA) of ventricular arrhythmias arising from the aortic sinus and/or the left ventricular summit. However, few studies have investigated the role of the atrial potentials in GCV-AIV in RFA procedure.Methods: N/AResults: A 38 year-old male underwent RFA of long RP’ narrow QRS tachycardia (cycle length 330ms). Because the earliest atrial activation during the tachycardia was recorded in the distal coronary sinus, a multielectrode catheter was further positioned in GCV-AIV. The atrial bipolar electrogram in AIV preceded the onset of the P wave by 35ms, and a uni-polar electrogram exhibited a near QS pattern. The left atriography and three-dimensional CT demonstrated that GCV-AIV was located along with the left atrial appendage (LAA) in a longitudinal direction (Figure), which indicated that the atrial potentials recorded in GCV-AIV reflected the potentials of LAA covering from the base to the tip. Since VA conduction was absent, the tachycardia was diagnosed as atrial tachycardia. LAA was mapped. The earliest activation site (-40ms) in LAA where RFA was successful was contiguous to the site of the earliest activation in AIV (Figure). Pacing from different sites including the left atrium and the pulmonary veins confirmed that the atrial potentials in GCV-AIV were the far-field LAA potentials.Conclusion: Because of the anatomical relationship, the atrial potentials in GCV-AIV may be useful not only to diagnose LAA tachycardia but also to approximate the site of tachycardia origin in LAA.


cardioverter defibrillator (ICD) was performed at 63 years old because of severe family history of sudden cardiac death (two of his sons at 32 and 22 years old). Patients 2: an eighteen years old man had been resuscitated from VF during exercise, and was diagnosed as IVF because no type-1 Brugada ECG at baseline and pilsicainide challenge test. PCCD was excluded because he exhibited no atrioventricular block or bundle branch block. His-ventricular interval was prolonged (93ms), and PES also induced VF. Although no further VF episodes were documented during the following 3 years, intraventricular conduction was progressively impaired; QRS width was prolonged from 98ms to 132ms. To functionally characterize the frameshift mutartion V1764fsX1786, mutant or wild-type sodium channel were heterologously expressed in HEK-293 cells using whole cell patch clamp technique. Cells expressing V1764fsX1786 showed no observable Na current.Conclusion: A significant phenotypic overlap was found between IVF and PCCD in the two probands with the V1764fsX1786, loss-of-function frameshift mutation of cardiac sodium channel SCN5A.

by brief sinus acceleration without clear ictal pattern on EEG. The features suggest possibility of a deep seizure focus triggering sympatho-vagal discharge and consequent asystole without surface EEG abnormalities or a cardioinhibitory form of vasovagal syncope without a triggering seizure. The patient was empirically loaded with intravenous leveritacetam with complete suppression of asystole for 48 hours. Leveritacetam was then discontinued following which recurrent EEG negative asystole developed within 48 hours. Leveritacetam was reinitiated at 500mg bid with complete suppression of events for 5 months so far.Conclusion: Cardio-inhibitory syncope may be a primary vasovagal phenomena or may occur secondary to seizure. The presence of a negative seizure evaluation does not fully exclude a syndrome responsive to antiepileptic therapy.

PO02-188

VARIABLE EXPRESSIVITY OF PHENOTYPE IN THE V1764FSX1786 MUTATION OF CARDIAC SODIUM CHANNEL SCN5AHiroshi Kawakami, MD, Takeshi Aiba, MD, PhD, Hideki Okayama, MD, PhD, Yukio Kazatani, MD, PhD, Ikutaro Nakajima, MD, Koji Miyamoto, MD, Yuko Yamada, MD, Hideo Okamura, MD, Takashi Noda, MD, PhD, Kazuhiro Satomi, MD, PhD, Shiro Kamakura, MD, PhD, Naomasa Makita, MD, PhD and Wataru Shimizu, MD, PhD. National Cerebral and Cardiovascular Center, Suita, Japan, Ehime Prefectural Central Hospital, Matsuyama, Japan, Nagasaki University, Nagasaki, JapanIntroduction: Mutations in cardiac sodium channel α-subunit gene SCN5A result in multiple inherited arrhythmic syndromes such as long QT syndrome type 3 (LQT3), Brugada syndrome, progressive cardiac conduction defect (PCCD) and idiopathic ventricular fibrillation (IVF). Furthermore, even in the same mutation (eg. E1784K) of SCN5A, different phenotypes such as LQT3 and Brugada syndrome are observed. In this study, we show two unrelated probands carrying the same SCN5A frameshift mutation V1764fsX1786 who exhibit distinct clinical manifestations; PCCD and IVF.Methods: N/AResults: Patient 1: a forty-seven years old man had recurrent syncope due to advanced atrioventricular block and sick sinus syndrome. He was diagnosed as PCCD because of a severe intraventricular conduction delay (QRS width = 200 ms). Although VT/VF was not induced by programmed electrical stimulation (PES), a prophylactic implantation of implantable

S217

POSTER PO03: Poster Session IIIThursday, May 9, 20132 - 5 p.m.

PO03-01

MEASURING CHANGES IN AF DYNAMICS WITH ABLATION: IS THE MEAN ATRIAL CYCLE LENGTH SUFFICIENT?Simon Stolcman, BSc, Anthony G. Brooks, PhD, Lauren Wilson, BSc, Pawel Kuklik, PhD, Melissa E. Middeldorp, Rajiv Mahajan, MD, Rajeev Pathak, MBBS, Anand N. Ganesan, MBBS, PhD, Sachin Nayyar, MD, Darragh Twomey, MBBS, Kurt C. Roberts-Thomson, MBBS, PhD, Glenn D. Young, MBBS and Prashanthan Sanders, MBBS, PhD. Centre for Heart Rhythm Disorders, University of Adelaide and Royal Adelaide Hospital, Adelaide, AustraliaIntroduction: A gradual or stepwise increases in atrial cycle length (CL) has been observed with ablation of atrial fibrillation (AF) and often heralds arrhythmia termination. We sought to explore various cycle length parameters in patients who terminate during ablation.Methods: Twenty-nine patients (59±10yrs) undergoing catheter ablation for AF (long-standing persistent=3, persistent=13, paroxysmal=13) were studied. Patients were selected on the basis that they were in AF for ≥10mins and terminated directly to sinus rhythm during ablation. Thirty second AFCL samples were measured from coronary sinus electrograms before ablation and pre-termination by 2 examiners. The mean, standard deviation and coefficient of variation (COV) of the fibrillatory intervals (FI) were calculated. In addition, the percentage of FIs above the 95th percentile at baseline was determined prior to termination.Results: Mean and standard deviation of FIs significantly increased from baseline to pre-termination (178±17ms vs. 203±25ms; p=<0.001), with 25/29 (86%) patients demonstrating an increase in mean AFCL (>5msec) prior to termination. The percentage of longer coupled FIs increased significantly (5±0.3 vs. 21±15; p=<0.001) prior to termination. The COV of the FIs did not change pre-termination compared to baseline (21±6 vs. 20±5; p=0.68).Conclusion: Significant changes in mean AFCL and longer coupled FIs were present pre-termination. Of note, the increase in both mean and standard deviation of the FIs pre-termination (resulting in no change in COV) may suggest that although the FI increases, underlying beat-to-beat entropy persists.

PO03-02

TRANSIENT PROLONGED QTC INTERVAL IN PATIENTS FOLLOWING SURGICAL INTERVENTIONDaniel D. Joyce, BA, Kristina H. Haugaa, MD, PhD, J. Martijn Bos, MD, PhD, Robert F. Tarrell, MS, Bruce W. Morlan, MS, Pedro J. Caraballo, MD and Michael J. Ackerman, MD, PhD. Mayo Clinic, Rochester, MNIntroduction: Since QT prolongation is an independent risk factor for cardiovascular mortality and considering that QT inciting factors may be modifiable, Mayo Clinic developed an institution-wide clinical decision algorithm alerting the provider if QTc is > 500 ms. Herein, we performed a subset analysis on patients whose ECG was alerted for QT prolongation in the first 24 hours after a surgical procedure.Methods: Between 11/2010 through 06/2011, 86,107 ECGs were performed on 53,291 patients and 470 patients (0.9%) exhibited an electrocardiographically isolated QTc > 500 ms. The electronic medical record (EMR) was reviewed for the 86

(18%) patients (41 male, average age 55 ± 27 years, mean QTc 515 ± 25 ms) whose first alerted QTc occurred in the first 24 hours following surgery. The EMR was reviewed for conditions associated with QT-prolongation, electrolyte disturbances and known QT-prolonging drugs.Results: The average pre-operative QTc of these patients was 458 ± 30 and a post-operative QTc increase of 56 ± 35 ms was observed. While resolved in most patients, QT prolongation persisted at the time of discharge in 14 patients (16%). Most patients (79, 92%) had ≥1 known QT inciting factor. Notably, 7 patients (8%) had no identifiable QT aggravating condition, electrolyte disturbance, or medications prior to surgery. Of these 7, intra-operative records demonstrated 3 received a tier 2 (possible torsades) drug and 1 experienced abnormal electrolytes during the procedure. Of the 3 remaining patients with idiopathic QTc prolongation, 2 were male, with an average age 57 ± 36 years and mean QTc of 515 ms with an average increase of 30 ms. Of the surgeries performed, 2 were cardiac and 1 was non-invasive orthopedic. In all patients, QT prolongation resolved before discharge.Conclusion: Transient QT prolongation following surgery was the setting for nearly 1 of every 5 QTc alerts with the majority having identifiable QT inciting factors. While idiopathic, transient QT prolongation was seen in a select few, the majority could be explained by known etiological factors suggesting that maladaptive cardiac repolarization is most likely not a transient, post-operative stress response.

PO03-03

THE CHANGING DYNAMICS OF ATRIAL CYCLE LENGTH PRIOR TO TERMINATION OF AF DURING CATHETER ABLATIONSimon Stolcman, BSc, Anthony G. Brooks, PhD, Lauren Wilson, BSc, Pawel Kuklik, PhD, Melissa E. Middeldorp, Anand N. Ganesan, MBBS, PhD, Rajiv Mahajan, MD, Rajeev Pathak, MBBS, Sachin Nayyar, MD, Darragh Twomey, MBBS, Kurt C. Roberts-Thomson, MBBS, PhD, Glenn D. Young, MBBS and Prashanthan Sanders, MBBS, PhD. Centre for Heart Rhythm Disorders, University of Adelaide and Royal Adelaide Hospital, Adelaide, AustraliaIntroduction: Increases in atrial cycle length (CL) from baseline to pre-termination have been well documented during atrial fibrillation (AF) ablation. We sought to examine temporal evolution of AFCL during the 10mins prior to termination.Methods: Ten patients (62±9yrs) undergoing catheter ablation for AF (persistent=6, paroxysmal=4) were studied. Patients were in sustained AF prior to ablation and terminated directly to sinus rhythm during ablation. An export of CS electrograms 10mins prior to termination was measured for AFCL by 2 researchers. The final 10 fibrillatory intervals (FI) before termination were excluded. The sample was divided into 60 epochs for which the mean and standard deviation of the FIs were calculated. In addition, the number of FIs above the 95th percentile at baseline was determined.Results: The mean of 60 consecutive 10sec epochs demonstrated significant statistical epoch-to-epoch variability (p<0.001 in 9/10pts); however, no patient demonstrated a consistent change in these statistics prior to termination. The mean proportion of longer-coupled FIs (i.e. >95th percentile at baseline) was also associated with epoch-to-epoch variability in each patient (p<0.05 in 8/10pts), but again there was no consistent increase in this statistic prior to termination in any patient.Conclusion: Unexpectedly, the mean, standard deviation and proportion of longer-coupled FIs exceeding the 95th percentile did not consistently change toward termination. Therefore, the


of 2 arrhythmia experts reviewed records for all PARA pts & confi rmed treatment was appropriate for all but would have further assessed 1 pt with lung disease.Conclusion: PARA treatment & discharge of pts with regular SVT is safe, effi cacious & reduces admissions.

PO03-05

NEWLY DIAGNOSED PAROXYSMAL ATRIAL FIBRILLATION; TRIGGERS OR SUBSTRATE?Geetanjali Rangnekar, BSc, Anthony G. Brooks, PhD, Melissa E. Middeldorp, Julia Kim, BSc, Emilie Rasheed, Karen Drury, Elena Pancewicz, BSc, Scott Willoughby, PhD, Kurt Roberts-Thomson, MBBS, PhD and Prashanthan Sanders, MBBS, PhD. The University of Adelaide, Adelaide,SA, AustraliaIntroduction: First onset atrial fi brillation (AF) may arise due to established sub clinical cardiac remodelling. Little is known about the substrate associated with newly diagnosed paroxysmal AF.This study characterised the degree of abnormal left atrial (LA) substrate and trigger in fi rst onset paroxysmal AF (pAF) patients and arrhythmia free controls.Methods: 32 newly diagnosed pAF patients (Disease Hx≤3 months) were recruited from a University hospital. Age matched (± 5 years) arrhythmia free controls (n=32) were recruited via a newspaper advertisement. Patients underwent 7 day ambulatory ECG and Echocardiography to determine arrhythmia/trigger burden and LA measurements.Results: New pAF patients did not differ in their demographics (gender, body mass index and body surface area, P>0.05) and co morbid disease profi le with the exception of hypertension being over represented in the diseased group (75% vs 19%).Atrial trigger burden was higher in the newly diagnosed pAF (P=0.03). Majority of LA dimensions (diameter, major, minor, and volume) dimensions were not signifi cantly different; however LA area did reach statistical signifi cance (P=0.03) (Figure).Conclusion: New pAF patients exhibit similar LA dimensions even though they are more often hypertensive. Conversely, trigger burden was a distinguishing feature between the groups, which could indicate triggers precede LA dilatation in the temporal evolution of AF.

PO03-06

INAPPROPRIATE INHIBITION DURING LV THRESHOLD TESTINGMarc A. Dutro, RN, Cardiac Rhythm Device Services, The Ohio State University Wexner Medical Center. The Ohio State University Wexner Medical Center, Columbus, OHIntroduction: A 71 y/o male was referred for direct admission to The Ohio State University Wexner Medical Center by his local cardiologist for left ventricular lead revision in May 2011. His original system was implanted in 2009 and the generator was replaced in 2008. The physician stated that interrogation in his offi ce showed LV non-capture. Upon admission an inpatient ICD interrogation was performed by the device clinic nurse. The atrial and RV lead function was normal. Underlying rhythm

use of FIs may yield limited information about AF complexity and/or probability of AF termination.

PO03-04

SAFETY AND EFFICACY OF PARAMEDIC TREATMENT OF REGULAR SUPRAVENTRICULAR TACHYCARDIAVictoria Baker, MSc, Mark Whitbread, MSc, Laura Richmond, MSc, Claire Kirkby, MSc, Gemma Robinson, MSc, Sotiris Antoniou, MSc and Richard Schilling, MD, MBBS. Barts Health NHS Trust, London, United Kingdom, London Ambulance Service NHS Trust, London, United KingdomIntroduction: Paramedic administration of adenosine to treat supraventricular tachycardia (SVT) prior to hospital transfer has been proven safe. We hypothesised that paramedics can safely treat & discharge pts with regular SVT without transfer to hospital & tested this in a randomised controlled trial.Methods: Heamodynamically stable pts presenting with regular narrow complex tachycardia on 12 lead ECG, with no history of structural or ischaemic heart disease & no contraindication to adenosine were considered for enrolment. Pts were randomised to paramedic (PARA) or hospital (A&E) treatment.PARA pts received valsalva manoeuvre at the scene with administration of 6mg & 12mg of adenosine unless the SVT terminated. Pts were taken to A&E if the tachycardia did not terminate, restarted, or the patient had continuing symptoms, a persistently abnormal ECG (except T wave inversion) or heamodynamic instability. Prior to PARA discharge pts received information & a referral letter for their medical practitioner to arrange an arrhythmia clinic referal.Pts randomised to A&E were treated as normal & given no information other than that pertaining to the study.Data was collected from the paramedics, A&E notes & 6 month telephone interview.Results:

A&E PARA P valueNo. of pts 33 25 P < 0.4Average age 53 + 18 50 + 19 NSLost to Follow up 1 1 NSParamedic time with patient (min) 43 + 17 84 + 41 P <

0.0001Ambulance arrival to discharge home (min)

2424 + 6272

480 + 729 P < 0.09

Pts given copy of arrhythmia ECG (%) 62% 94% P < 0.03Pts given written SVT information (%) 38% 94% P <

0.0003

12 of 25 pts randomised to PARA were still taken to A&E (5 did not terminate arrhythmia, 1 abnormal observations, 4 with abnormal ECG (judged minor abnormalities not requiring treatment), 2 abnormal ECG requiring treatment). A panel

S219Poster Session III

PO03-08

IMPLANTATION OF A LEADLESS PACEMAKER WITHIN REANIMATED HUMAN HEARTS USING DIRECT VISUALIZATIONMichael D. Eggen, PhD, Matthew D. Bonner, PhD, Todd J. Sheldon, MS, Eric R. Williams, BS and Paul A. Iaizzo, PhD. Medtronic, Mounds View, MN, University of Minnesota, Minneapolis, MNIntroduction: Recently, we have created a 7-year VVIR pacemaker with a volume less than 1 cc that can be placed directly within the heart. Typical preclinical animal models for the development of pacemakers and leads include canine, ovine, and swine. Although the functionality of this device has been tested in chronic sheep studies, one anatomical limitation is that the RV endocardial surface of animal models is markedly less trabeculated than human. In this study, we acutely tested the electrode tissue interface and fixation of this pacemaker using direct visualization within reanimated human hearts, and measured the resultant pacing thresholds.Methods: Five human donor hearts, deemed not viable for transplantation, were perfused with a clear Krebs-Henseleit buffer and reanimated using the Visible Heart® Methodologies. Following reanimation, either wired or functional capsules were implanted in the RV via access through the SVC using both fluoroscope and intracardiac endoscopes (for direct visualization) to record the device position and deployments. For the first deployment within each heart, the pacing thresholds (@ 0.5 ms) were tested using the Medtronic 2290 pacing system analyzer for wired devices (n=3), or the Medtronic 2090 programmer (@ 0.24 ms) for functional devices (n=2).Results: The pacing thresholds can be seen in Figure 1, with an endoscopic image from a typical implant. In each heart, the device was able to fixate and obtain a low pacing threshold with the first implant.Conclusion: From this study we conclude that the pacing thresholds are low, and the profile and fixation mechanism of this pacemaker are sufficient to navigate and fixate to the endocardium of the highly trabeculated human RV.

was sinus with a significant intraventricular block (214ms) on 12-lead ECG. Upon testing the LV lead it was observed that the lead capture appropriately for one beat, but the next cardiac cycle would be inhibited on the surface ECG. This cycle would then repeat for the duration of the LV capture threshold test. By carefully examining the IEGMs during the LV threshold testing it was discovered that the left-to-right intraventricular conduction delay while pacing the LV only was 300-320ms. Medtronic CRT devices sense the ventricular activity from only RV lead. The long delay then fell outside the blanking and refractory periods, resulting in functional oversensing and inhibition of the pacemaker. Once this was discovered the LV capture threshold was repeated in asynchronous (DOO) mode and the capture threshold was found to be [email protected]. The patient was able to be discharged home without requiring further intervention.Conclusion: This case study serves to demonstrate the importance of performing thorough evaluations by experienced personnel.

PO03-07

ARE PACEMAKER NOMINAL ATRIOVENTRICULAR DELAYS ADEQUATE DURING EXERCISE?Raul Chirife, MD, Cristina Tentori, MD and Aurora Ruiz, MD. Hospital Fernández, Buenos Aires, ArgentinaIntroduction: Long PR intervals may be inconsequential at rest, but at faster heart rates (HR) during exercise (Ex) left atrial contraction may overlap with isovolumic relaxation of the preceding beat causing “pacemaker syndrome (PMS) without a pacemaker”. Since actual AV during atrial sensing-right ventricular pacing (AS-RVP) is longer than programmed due to P-wave sensing offset, and RVP lengthens electromechanical systole, it was hypothesized that nominal AVs may be hemodynamically deleterious on Ex. To test this hypothesis Doppler echocardiography during Ex was used.Methods: A total of 29 Pts (62% males, median age 65+/-14) were studied by mitral Doppler inflow during mild recumbent leg exercise (Ex), first with AS-RVP AV delays of 150 ms representing a standard nominal setting, and then with optimized AV (AVopt) calculated according to a previously published equation and ranging from 50 to 100 ms. A deleterious hemodynamic effect was considered present when: a) mitral Doppler A-wave was fully fused with E-wave, or b) Doppler A-wave onset was earlier than E-wave onset, indicating atrial transport block (ATB).Results: 1. With nominal AVs 17 Pts reached HR >80 bpm during Ex, and of these 9 (34.6%) had Doppler E+A fusion and 2 Pts had ATB. 2. With AVopt 13 Pts reached HR >80 bpm, and none had either E+A fusion or ATB on exercise (P=0.016).Conclusion: 1. AS-RVP AVs of 150 ms or longer are hemodynamically deleterious for an important proportion of Pts during mild exercise. 2. AVopt had no adverse hemodynamic effect during Ex.


Introduction: It is widely believed that patients with more advanced heart failure (HF) symptoms are less likely to die from a cardiac arrhythmia and therefore would not benefit from ICD implantation. Using the Israeli ICD Registry data, we sought to examine the effect of HF functional class on the outcome of patients who receive device therapy in a real world setting. Methods: Between July 2010 and June 2012 a total of 2108 consecutive patients (84% male, mean age 64.9± 12) undergoing ICD/CRT-D implantation for primary prevention indications were prospectively enrolled in the Israeli ICD Registry. NYHA class < III was present in 1307 (62%) and class ≥ III in 801 patients (38%). A subset of 1218 unselected registry patients was prospectively followed for a median period of 317 days for the occurrence of appropriate ICD therapy and hospitalization for HF.Results: Patients with higher NYHA were older, had more co-morbid conditions, lower LVEF, wider QRS duration and were more likely to receive CRTD therapy (all p<0.001). Kaplan-Meier survival analysis showed that among ICD recipients the risk of appropriate device therapy for ventricular tachyarrhythmias was similar in the 2 NYHA groups (P=0.16). The risk for the development of HF events during follow-up was different between ICD and CRTD recipients. In the former group patients with NYHA≥III were more likely to develop HF events during follow-up (HR= 2.82; p<0.01), whereas among CRTD recipients the risk for the development of HF events was similar between the 2 groups (HR=1.15; P=0.74)Conclusion: Based on a large cohort of real-life ICD/CRTD multicenter registry, there is no evidence that severe heart failure patients are less likely to benefit from ICD therapy. Our data suggest that the association between advanced NYHA class and development of HF is attenuated among patients implanted with CRT-D devices.

PO03-11

LEFT VENTRICULAR DYSSYNCHRONY PREDICTS VENTRICULAR TACHYARRHYTHMIAS IN PATIENTS WITH SEVERELY REDUCED LEFT VENTRICULAR SYSTOLIC FUNCTIONSaurabh Malhotra, MD, MPH, Deepak K. Pasupula, MBBS, Samir Saba, MD, David Schwartzman, MD and Prem Soman, MD, PhD. University of Pittsburgh, Pittsburgh, PAIntroduction: Left ventricular (LV) ejection fraction (EF) alone has a limited ability to predict occurrence of ventricular tachyarrhythmias (VTs) among patients with severely reduced LVEF. LV dyssynchrony (LVD) has been reported in patients with low LVEF, and can be reliably assessed using Phase Analysis (PA) of gated single photon emission tomography (GSPECT) images. The association between LVD and VTs has not been well studied.Methods: We identified 128 patients (106 men; mean age: 63 + 14 years and mean LVEF: 23 + 7), who received an implantable cardioverter defibrillator (ICD) for primary prevention of sudden cardiac death and who also underwent a GSPECT study prior to ICD implantation. PA of the GSPECT images was performed using the SyncToolTM software (Syntermed, Inc., Atlanta, GA). LVD was said to be present if either the phase histogram bandwidth (HBW) or the phase standard deviation (PSD) >2 standard deviations above the mean normal published values. Occurrence of VTs was determined through routine ICD interrogations and electronic medical records.Results: LVD was present in 90 (70%) patients. VTs occurred in 25 (20%) patients, all of whom had LVD. None of the patients without LVD experienced VTs (figure). In a multivariable logistic analysis, summed rest score (OR, 95% CI: 1.07, 1.02-1.10), LV end-diastolic volume (1.01, 1.00-1.20) and female gender (0.03,

PO03-09

CHRONIC FISH OIL SUPPLEMENTATION IN THE ELDERLY DOES NOT SUPPRESS ATRIAL FIBRILLATION BURDEN: RESULTS FROM A PROSPECTIVE RANDOMIZED STUDYSaurabh Kumar, MBBS, Justin Lee, MD, Irene Stevenson, MBBS, Fiona Sutherland, RN and Paul B. Sparks, MBBS, PhD. The Royal Melbourne Hospital, Melbourne, AustraliaIntroduction: Epidemiological studies indicate reduced risk of incident AF in the elderly with increased fish consumption. We investigated if long-term fish oils reduce paroxysmal AF burden in the elderly with sinoatrial node disease and dual chamber pacemakers.Methods: Following a run-in period of 6 months (p1) where AF burden was logged, 78 patients were randomized to control or fish oil groups and fish oil commenced at 6g/d. AT/AF burden evaluated after 6 months (p2) in 39 controls and 39 fish oil patients and after 12 months (p3) in 39 controls and 18 fish oil patients. A subset of 21 fish oil patients crossed over to controls in the final 6 months (crossover group).Results: (i) Median AF burden increased significantly in controls (P<.001) but not in fish oil patients at 6 months (P=.5) or 12 months (P=.2); (ii) time to AF recurrence was not significantly different between the groups (P=.9); (iii) fish oil patients had similar frequency but shorter duration of AF episodes compared to controls; (iii) crossover patients experienced a rebound increase in AF burden (P=.01) reaching a level similar to controls in the final 6 months (crossover vs. controls, P=.63); (iv) crossover patients had higher AF burden than patients continuing fish oil for 12 months (crossover vs. continued intake, P = .02; Figure). Significant gastrointestinal side effects were reported in 36% of patients.Conclusion: Long-term fish oils did not suppress AF burden in the elderly. They may have attenuated temporal progression of AF related to aging and sinus node disease. Fish oils were poorly tolerated in this population. Clinical trials.gov NCT00232245

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OUTCOME OF PATIENTS WITH ADVANCED HEART FAILURE WHO RECEIVE DEVICE-BASED THERAPY FOR PRIMARY PREVENTION OF SUDDEN CARDIAC DEATH: INSIGHTS FROM THE ISRAELI ICD REGISTRYMahmoud Suleiman, MD, Guy Amit, MD, Nimer Samniah, MD, Natalie Gavrielov-Yusim, MSc, Raphael Rosso, MD, Alexander Pekar, MD, Doron Aronson, MD, Shlomit Ben-Zvi, MSc, Ilan Goldenberg, MD and Michael Glikson, MD. Rambam Medical Center, Haifa, Israel, Soroka University Medical Center, Beer-Sheva, Israel, Bnai Zion Medical Center, Haifa, Israel, IACT-Neufeld Cardiac Research Institute, Te- Aviv, Israel, Sourasky Tel-Aviv Medical Center, Tel-Aviv, Israel, Rivka Ziv Hospital, Tzfa, Israel, IACT-Neufeld Cardiac Research Institute, Tel-Aviv, Israel, Sheba Medical Center, Tel Hashomer, Israel


PO03-13

TERMINATION OF VENTRICULAR ARRHYTHMIAS IN PATIENTS WITH HYPERTROPHIC CARDIOMYOPATHYMark S. Link, MD, FHRS, Katy Bockstall, MD, Jonathan Weinstock, MD, Martin S. Maron, MD, Tammy S. Haas, BS, Christopher Semsarian, MD and Barry J. Maron, MD. Tufts Medical Center, Boston, MA, Minneapolis Heart Institute, minneapolis, MN, Department of Cardiology, Royal Prince Alfred Hospital, Sydney, Australia, Minneapolis Heart Institute, Minneapolis, MNIntroduction: Patients with hypertrophic cardiomyopathy (HCM) are at risk for ventricular arrhythmias and sudden cardiac death and often receive implantable defibrillators. However, the termination of the ventricular arrhythmias is poorly characterized.Methods: Termination of arrhythmias from patients with ICDs and ventricular arrhythmias were analyzed independently by 3 individuals and differences in analysis were resolved by consensus. Ventricular fibrillation (VF) was defined as a ventricular arrhythmia with ventricular rates > 220 beats/min (cycle length < 272 ms) in which intracardiac morphology varied from beat to beat. Ventricular tachycardia (VT) was defined as a monomorphic regular tachycardia with a CL > 260 msand ventricular flutter (VFL) was defined as VT with a CL < 260 ms.Results: Of 149 ventricular arrhythmias in 81 patients, 58 were VT, 17 VFL and 74 VF. In 45 episodes of VT, antitachycardia pacing was attempted and was successful in 33. In the 2 episodes of VFL in which ATP was attempted both were successful. Twenty-one of 112 ventricular episodes required more than 1 shock to terminate and multiple shocks were more often required for VFL (9/15 compared to 10/72 with VF and 3/25 with VT) (p<.0001).Conclusion: Monomorphic VT is as common in patients with HCM as is VF. This VT is often terminated by ATP. VFL is more difficult to terminate with shocks as compared to slower VT and VF. ICD programming for HCM patients should include ATP for all monomorphic ventricular tachycardias and high energy shocks.

PO03-14

ASSESSMENT OF RISK FOR HIGH DEFIBRILLATION THRESHOLDS IN 1509 PATIENTS: IS THE IMPLANTATION OF DOUBLE COIL ICD NECESSARY?Goetz Buchwalsky, MD, Klaus Langes, MD, Juergen Siebels, MD, Marius Volkmer, MD, Wolfgang Duckeck, MD, Joachim Hebe, MD, Christoph Heuser, MD, Stephan Willems, MD, Ali M. Aydin, MD and Rodolfo Ventura, MD. Elektrophysiologie Bremen am Klinikum Links der Weser, Bremen, Germany, Abteilung für Kardiologie/Elektrophysiologie, Universitäres Herzzentrum Hamburg, Hamburg, GermanyIntroduction: High defibrillation thresholds (DFT) can compromise the function of implantable cardioverter defibrillators

0.01-0.32) were significant independent predictors of LVD. LVEF, QRS duration and presence of left bundle branch block did not predict LVD.Conclusion: LVD assessment by GSPECT is highly predictive of VTs in patients with low LVEF.

PO03-12

COMPARISON OF THERAPY WITH AMIODARONE OR IMPLANTABLE CARDIOVERTER DEFIBRILLATORS FOR SECONDARY PREVENTION OF MORTALITY IN CHAGAS’ HEART DISEASEAlvaro V. Sarabanda, MD, PhD, Wagner L. Gali, MD, Jose M. Baggio Jr, MD, Luis G. Ferreira, MD, Gustavo G. Gomes, MD, Jose A. Marin-Neto, MD, PhD and Luiz F. Junqueira Jr, MD, PhD. Instituto de Cardiologia do Distrito Federal (IC-DF), Brasilia DF, Brazil, Medical School of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP, Brazil, University of Brasilia (UNB), Brasilia DF, BrazilIntroduction: Evidence is inconclusive concerning the role of ICD for secondary prevention in Chagas’ heart disease (ChHD).Methods: We compared the outcomes of 76 consecutive pts with ChHD (48 men; age, 57±11 years; LVEF, 39±12 percent) who received an ICD for therapy of sustained ventricular tachycardia (VT) with those of an historical group of 28 chagasic pts (18 men; age, 54±10 years; LVEF, 41±10 percent) presenting with sustained VT treated with amiodarone alone.Results: The ICD pts and the non-ICD pts had comparable baseline characteristics, except for a higher proportion of therapy with beta-blockers (90 percent versus 17 percent, P<0.0001) in the ICD group. During the follow-up period (33 ± 16 months for the ICD group and 35 ± 17 months for the non-ICD group; P = 0.22), there were 10 deaths (4.7 percent annual mortality rate) in the ICD group and 9 deaths (11 percent annual mortality rate) in the control group. ICD therapy was associated with a decreased risk of death of 72 percent (hazard ratio, 0.28; 95 percent confidence interval, 0.11 to 0.72; P = 0.007) and an absolute decrease in the mortality rate of 18 percentage points after three years. A LVEF < 40 percent was a predictor of worse prognosis, and was associated with a risk of death that was increased by a factor of more than 6 (hazard ratio, 6.63; 95% CI, 2.12 to 20.0; P=0.007). In the ICD group, 52 pts (72 percent) received appropriate ICD therapies, and 8 (11 percent) received inappropriate shocks.Conclusion: In chagasic pts with sustained VT, ICD therapy significantly reduced the risk of death from any cause by 72 percent, as compared with a control group of chagasic pts treated with amiodarone alone. Pts with LVEF < 40% derive the most survival benefit from ICD therapy.


CHA2DS2-VASc scores and the incidence and burden of AHRE was explored in the initial 2,359 patients observed for 3,733 patient-years, blinded to treatment assignment. The AHRE burden was calculated as the percent time spent in AHRE for each patient who had any AHRE.Results: Patients were 74% male, with coronary disease in 72%, CHF in 90% and EF of 30 ± 11%. The incidence (bars) and burden (lines) of AHRE are shown in the Figure. The incidence of AHRE was 31% in the entire cohort, with little variation based on CHA2DS2-VASc score. The mean AHRE burden was 3% for subjects with at least 1 AHRE, and there was no systematic effect of the stroke risk scores. Only results for CHA2DS2-VASc scores are shown, but the results were similar sorting subjects by CHADS2 scores.Conclusion: The frequency of AHRE events is distributed equally across the range of CHADS2 and CHA2DS2-VASc scores, suggesting that the greater stroke risk for patients with higher risk scores is not due to a greater incidence or burden of AHRE.

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COMPLEXITY OF SCAR ASSESSED WITH LATE GADOLINIUM ENHANCEMENT CARDIOVASCULAR MAGNETIC RESONANCE AS AN INDEPENDENT SPECIFIC PREDICTOR OF APPROPRIATE IMPLANTABLE CARDIOVERTER DEFIBRILLATOR THERAPY DELIVERY IN DILATED CARDIOMYOPATHYMaurizio G. Lunati, MD, Stefano Pedretti, MD, Ederina Mulargia, MD, Corrado Ardito, MD, Sara Vargiu, MD, Patrizia Pedrotti, MD, Davide Ottolina, MS, Silvia Bisetti, MS and Alberto Roghi, MS. Niguarda Ca’Granda, Milano, Italy, Metronic Italia, Milano, ItalyIntroduction: To assess late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging characteristics yelding a high risk of ventricular arrhythmias and appropriate implantable cardioverter defibrillator (ICD) therapy delivery in patients implanted for sudden cardiac death (SCD) primary or secondary prevention.Methods: From Jan. 1st, 2006 to Dec. 31st, 2010, 96 consecutive patients receiving an ICD (84 for primary prevention; 47 affected from ischemic cardiomyopathy) and previously evaluated with CMR were enrolled. Left ventricular (LV) and right ventricular (RV) volumes and ejection fraction (EF) were evaluated, as well as late gadolinium enhancement imaging. LGE was defined “complex” (Cx-LGE) in presence of one of the following: 1) ischemic pattern, involving ≥ 2 different coronary territories; 2) epicardial distribution; 3) “diffuse” subendocardial; 4) presence of ≥ 2 different patterns. Patients were regularly followed and appropriate ICD interventions were detected. The primary end-point was the occurrence of a sustained ventricular arrhythmia requiring an ICD therapy. A composite secondary end-point of cardiovascular death, cardiac transplantation or ventricular assist device implantation was also considered.Results: During a median follow-up of 30 months, 21 (22%) and 17 (18%) patients reached the primary and secondary end-

(ICD) and the patient safety. Assessment of potential risk factors for high DFT may improve the patient care.Methods: We assessed potential risk factors for high DFT in a retrospective analysis of unselected patients (pts) undergoing the first ICD implantation for primary or secondary prevention of sudden cardiac death in our institution. All pts undergoing generator replacement or lead revision as well as those with contraindication for defibrillation testing (DT) were excluded. A DT was performed in all study pts. Successful DT was defined, when the first shock was able to terminate ventricular fibrillation at an energy value of at least 10 Joule below the maximum ICD output. In a multivariate analysis the following factors were evaluated: gender, age, primary and secondary prevention, structural heart disease, EF, NYHA class, lead type (single-/dual coil), lead position, R-wave amplitude, lead impedance parameters and amiodarone therapy.Results: In the study were included 1509 pts (78.5% male; 61±13 years; EF 34±13%) undergoing ICD implantation between 1997 and 2010; 1481 (98%) had structural heart disease such as coronary artery disease (57.5%), dilative- (28%), hypertrophyc- (4%) and valvular cardiomyopathy (2%) or other organic alterations (8.5%). The ICDs (16% CRT-ICDs) were implanted in 523 (35%) pts for primary- and in 986 (65%) for secondary prevention. A single coil lead was implanted in 797 (53%) and a dual coil lead in 712 (47%) pts. At the time of the ICD implantation 42 (3%) pts were under amiodarone therapy. DT was successful in 1401 (93%) and unsuccessful in 108 (7%) pts. The multivariate analysis revealed only amiodarone (p=0.002) and a young age (56.9 vs 61.5 years, p<0.001) as independent predictors for unsuccessful DT. Implantation of a double coil ICD electrode did not prevent high DFT.Conclusion: Implantation of double coil ICD electrodes did not predict lower DFT as single coil electrodes. Pts under amiodarone and young pts demonstrated to be at risk of DFT independently of the electrode type. DT should not be omitted in these patients. Additionally, implantation of high energy ICD with a single coil electrode should be considered in all pts.

PO03-15

CAN THE CHADS2 OR CHA2DS2-VASC SCORE PREDICT OCCURRENCE OF ATRIAL ARRHYTHMIAS?Malcolm M. Bersohn, MD, PhD, David T. Martin, MD, Gregory Y.H. Lip, MD, Joseph G. Akar, MD, Wassim K. Choucair, MD, Albert L. Waldo, MD, Mark Wathen, MD, Crystal Miller, MS, Jonathan L. Halperin, MD, John Ip, MD, for the IMPACT Investigators. UCLA / VA Greater Los Angeles Healthcare, Los Angeles, CA, Lahey Clinic Medical Center, Burlington, MA, University of Birmingham Centre for Cardiovascular Sciences, Manchester, United Kingdom, Yale University School of Medicine, New Haven, CT, Cardiology Associates of Corpus Christi, Corpus Christi, TX, Case Western Reserve University, Cleveland, OH, Tennessee Heart, PLLC, Cookeville, TN, Biotronik, Lake Oswego, OR, Mount Sinai Medical Center, New York, NY, Thoracic & Cardiovascular Healthcare Foundation, Lansing, MIIntroduction: The CHADS2 and CHA2DS2-VASc scores provide clinical guidance for defining stroke risk for patients with atrial fibrillation (AF). It is not known if the increased stroke risk with higher scores is due to increased AF burden or other thromboembolic risks.Methods: IMPACT is a single-blind trial randomizing patients with either dual-chamber or resynchronization therapy ICDs to use or not to use remote monitoring of atrial high rate events (AHRE) to initiate and terminate anticoagulation, based on the AHRE burden and the CHADS2 score, which had to be at least 1 for study inclusion. The relationship between CHADS2 and


PO03-18

IS THE PRESENCE OF NON-SUSTAINED VENTRICULAR TACHYCARDIAS ASSOCIATED WITH TRUE VENTRICULAR TACHYCARDIAS AND VENTRICULAR FIBRILLATION IN PRIMARY PREVENTION PATIENTS?Paul D. Ziegler, MS, Shu Zhang, MD, Vanita Arora, MD, Athula Abeyratne, PhD, James Coles, Jr., PhD and Li Wang, PhD. Medtronic, Mounds View, MN, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, Max Heart & Vascular Institute, Saket, New Delhi-17, India, Medtronic (Shanghai) Management Co., Ltd., Pudong, Shanghai, ChinaIntroduction: The presence of non-sustained ventricular tachycardias (NSVT) may help identify a subset of primary prevention indicated ICD patients who are at greatest risk of having significant arrhythmias and therefore merit ICD implantation. However, the correlation between device-detected NSVT and true episodes of ventricular tachycardia or ventricular fibrillation (VT/VF) in the primary prevention population is not well understood.Methods: Device data between months 1 - 13 after ICD implant were analyzed from patients with a primary prevention indication. All recorded VT/VF episodes were adjudicated by expert review. The association between patients who had NSVT detected by the ICD (defined as ≥5 beats within the programmed VT or VF zone) and those who had true VT/VF was assessed by Pearson’s Chi-Square test. We also computed the sensitivity, specificity, positive predictive value, and negative predictive value of NSVT episodes to identify patients with true VT/VF episodes.Results: Among the 1135 primary prevention patients with continuous device data between months 1 and 13, a history of NSVT was present at baseline in 271 patients (23.9%). A total of 196 patients (17.3%) experienced at least one episode of true VT/VF and 765 patients (67.4%) had at least one episode of NSVT recorded by the device. The presence of NSVT recorded over the one year follow-up period correlated with a higher incidence of true VT/VF episodes recorded by the ICD (p<0.0001). The presence of device-detected NSVT episodes was highly sensitive (91.3%) but only modestly specific (37.6%) for identifying patients with true VT/VF. The positive and negative predictive values of device-detected NSVT episodes to identify patients with true VT/VF were 23.4% and 95.4%, respectively.Conclusion: A significant correlation exists between the presence of device-detected NSVT and true VT/VF episodes. The vast majority (91.3%) of patients with true VT/VF episodes also have device-detected episodes of NSVT. Furthermore, the absence of NSVT episodes via long-term continuous monitoring is highly predictive (95.4%) of the absence of true VT/VF episodes. These results suggest that extended periods of NSVT monitoring may be useful in identifying those patients who would benefit most from ICD implantation for primary prevention.

PO03-19

INTERMEDIATE BASELINE QRS DURATION IS ASSOCIATED WITH BETTER OUTCOMES AFTER CARDIAC RESYNCHRONIZATION COMPARED TO RELATIVELY NARROW AND VERY WIDE BASELINE QRS DURATIONEvan C. Adelstein, MD, David Schwartzman, MD, Sandeep Jain, MD, John Gorcsan, III, MD and Samir Saba, MD. University of Pittsburgh, Pittsburgh, PAIntroduction: QRS duration ≥120 ms is an established criterion for cardiac resynchronization (CRT), yet QRS ≥150 ms has been associated with greatest benefit. It is unknown if CRT outcomes

point, respectively. Only one patient experienced an ICD shock before heart transplantation. At univariate analysis, Cx-LGE was highly predictive of primary end-point occurrence (HR=3.79 [C.I. 95%:1.53-9.40], p=0.004), as well as implant indication in secondary prevention (HR=2.79 [C.I.95%:1.08-7.23], p=0.034) and NYHA class (HR=0.34 [C.I.95%:0.18-0.64], p<0.001); at a multivariate analysis, Cx-LGE and NHYA class were confirmed as strongly independent predictors of ICD interventions, respectively (HR=2.99 [C.I. 95%:1.06-8.44], p=0.039) (HR=0.41 [C.I. 95%:0.21-0.82], p=0.012). Cx-LGE complexity was not associated with secondary end-point (p=ns for univariate and multivariate analysis).Conclusion: Cx-LGE is a new, powerful, independent, specific, easily determined risk factor for ventricular arrhythmias and SCD in dilated cardiomyopathy of any etiology.

PO03-17

PREDICTORS OF MORTALITY IN THE MADIT-RIT TRIALAnne Christine H. Ruwald, MD, David Huang, MD, Ilan Goldenberg, MD, Valentina Kutyifa, MD, Martin H. Ruwald, MD, Claire Zhang, Scott McNitt, MS, Christian Jons, MD, Poul Erik Bloch Thomsen, MD, Wojciech Zareba, MD and Arthur J. Moss, MD. University of Rochester, Medical Center, Rochester, NY, Gentofte Hospital, Department of Cardiology, Hellerup, Denmark, Aalborg University, Faculty of Medicine, Aalborg, DenmarkIntroduction: The benefit of a novel ICD programming on inappropriate ICD therapy and mortality was demonstrated in MADIT-RIT. Therefore we aimed to identify the predictive value of baseline clinical characteristics, ICD programming, and time-dependent ICD therapy on mortality in the MADIT-RIT population.Methods: The MADIT-RIT study randomized 1500 patients with a primary prophylactic indication for ICD or CRT-D to one of three different ICD programming arms: A) conventional programming with VT zone ≥ 170 bpm; B) high-rate cut-off with VT zone ≥ 200 bpm; and C) prolonged 60 sec. delay before therapy. Multivariate Cox proportional hazards regression model with best subset regression was used to identify predictors of mortality in all 1500 patients.Results: During an average follow-up of 1.4±0.6 years, 71 out of 1500 (5%) patients died. Mode of death was cardiac in 40 patients (56.3 %), non-cardiac in 23 patients (32.4%) and unknown in 8 patients (11.3%). Time-dependent appropriate shock and inappropriate ATP were associated with increased risk of death (see Table). Conventional ICD programming (A) was identified as an independent predictor of death when compared with ICD programming with a VT zone ≥ 200 bpm (B), but not when compared to ICD programming with prolonged 60 sec delay (C) before therapy (see Table. The significant predictors of mortality identified in the MADIT-RIT trial are listed in the Table.Conclusion: Conventional ICD programming, inappropriate ATP, and appropriate shock are independently associated with increased mortality.


mortality in patients treated with CRT and to design a risk score for mortality.Methods: A cohort of 608 consecutive patients treated with CRT from 2000 to 2011 in our center was prospectively analyzed. Baseline clinical and echocardiography variables were analyzed and mortality data were collected.Results: During a mean follow-up of 36.2±29.2months, 174 patients died: 123/174 (71%) due to cardiovascular causes, 25/174 (14%) noncardiac causes and 26/174 (15%) unknown etiology. In a multivariate analysis the predictors of mortality -hazard ratio (HR) and 95% confidence interval (95%CI)-- were NYHA class IV HR 2.54 (95%CI 1.70-3.79, P<0.001), glomerular filter rate (GFR) <60 mL/min/1.73 m2 HR 1.61 (95%CI 1.14-2.29, P<0.01), atrial fibrillation (AF) HR 1.67 (95%CI 1.19-2.34, P<0.01), age HR 1.03 (95%CI 1.01-1.05, P<0.01) and EF HR 0.95 (95%CI 0.93-0.98, P<0.01). The EA2RN score (EF, Age, AF, Renal dysfunction, NYHA class IV) summarizes the predictors. Each additional predictor increased the mortality: one predictor, HR 3.27 (95%CI 1.37-7.8, P<0.01); two, HR 5.23 (95%CI 2.24-12.10, P< 0.001); three, HR 9.62 (95%CI 4.10-22.60, P<0.001) and four or more, HR 14.3 (95%CI 5.8-35.65, P<0.001).Conclusion: The predictors of mortality have a significant add-on predictive effect on mortality. The EA²RN score could be useful to stratify the prognosis of CRT patients.

PO03-21

AV-NODE ABLATION TO OPTIMIZE THE LEFT VENTRICULAR DESYNCHRONIZATION THERAPY IN HYPERTROPHIC OBSTRUCIVE CARDIOMYOPATHYDiego Penela, MD, Antonio Berruezo, MD, PhD, Reinder Evertz, MD, Juan Fernández-Armenta, MD, Ada Doltra, MD, Xavier Alsina, RN, Felip Burgos, MSc, Josep Roca, MD, PhD, Marta Sitges, MD, PhD, Lluis Mont, MD, PhD and Josep Brugada, MD, PhD. Arrhythmia Section, Cardiology Department, Thorax Institute. Hospital Clínic, Universitat de Barcelona, Barcelona, Spain, Cardiology Department, Thorax Institute. Hospital Clínic, Universitat de Barcelona, Barcelona, SpainIntroduction: In recent studies, biventricular pacing is the optimal pacing configuration in the vast majority of symptomatic patients with hypertrophic obstructive cardiomyopathy (HOMC). However, a non-prolonged native PR interval in these patients can result in incomplete left ventricular (LV) pre-excitation due to the fusion of the native QRS and the stimulated QRS.Methods: We analyzed the presence of fusion in 12 consecutive symptomatic patients with HOMC and significant left ventricular outflow tract (LVOT) obstruction in whom a biventricular pacing device was implanted. Fusion was defined as any change in the QRS morphology/axis between optimal AV/VV biventricular

improve continuously with longer baseline QRS duration, i.e. “wider is better”.Methods: We categorized 387 consecutive CRT-defibrillator (CRT-D) pts with QRS ≥120 ms, LVEF ≤35%, NYHA 2-3 heart failure, non-RBBB QRS pattern, and no significant coronary artery disease (CAD) according to pre-CRT QRS duration: 120-147 ms (<1 standard deviation [SD] below mean, n=60), 148-209 ms (mean ± 1 SD, n=272), and ≥210 ms (>1 SD above mean, n=55). CAD was defined as ≥80% coronary stenosis, prior revascularization, or prior myocardial infarction. Prespecified outcomes included survival free from transplant or ventricular assist device (VAD) and LV end-systolic volume (LVESV) change at ≥3 months relative to baseline in pts with paired echos (n=165).Results: Baseline findings included age 64 ± 14, 58% male, 26% diabetic, 87% ACE-I or ARB use, 83% β-blocker use, NYHA 2.9 ± 0.3, LVEF 23 ± 8%, and QRS duration 178 ± 31 ms. Pts with QRS 148-209 ms had more females and higher incidence of baseline LBBB compared to IVCD or pacing. Over 55 ± 30 months, 129 (33%) pts died or received a transplant or VAD. Survival free from transplant or VAD was longest in pts with QRS 148-209 ms compared to both QRS 120-147 ms and ≥210 ms (correcting for gender, HR 2.2, 95% CI 1.4-3.4; p=0.001 for both comparisons). Relative LVESV decrease was largest in pts with QRS 148-209 ms.Conclusion: Among CRT-D pts without CAD, survival free from transplant or VAD and relative LVESV decrease are greatest in pts with intermediate pre-CRT QRS duration compared to relatively narrow and very wide QRS duration.

PO03-20

EA²RN SCORE, A PREDICTIVE SCORE FOR MORTALITY IN PATIENTS RECEIVING CARDIAC RESYNCHRONIZATION THERAPY BASED ON PRE-IMPLANTATION RISK FACTORSMalek Khatib, MD, José M. Tolosana, MD, Emilce Trucco, MD, Roger Borras, BSc, M Ángeles Castel, MD, PhD, Antonio Berruezo, MD, PhD, Adelina Doltra, MD, Marta Sitges, MD, PhD, Elena Arbelo, MD, PhD, Maria Matas, RN, Josep Brugada, MD, PhD and Lluís Mont, MD, PhD. Arrhythmia Section, Cardiology Department, Thorax Institute. Hospital Clínic, Universitat de Barcelona, Barcelona, Spain, Cardiology Department, Thorax Institute. Hospital Clínic, Universitat de Barcelona, Barcelona, Spain, Echocardiography Laboratory, Cardiology Department, Thorax Institute. Hospital Clínic, Universitat de Barcelona, Barcelona, SpainIntroduction: The beneficial effects of cardiac resynchronization therapy (CRT) in patients with advanced heart failure, wide QRS and low left ventricular ejection fraction (EF) have been clearly established. Nevertheless, mortality remains high in some patients. The aims of our study were to identify the predictors of


Results: A total of 24 LV lead sites in 7 patients (4 classic LBBB, 3 atypical or non-LBBB) were analyzed. The mean r-value for correlation of mechanical and electrical delay was 0.94 (range: 0.83-1.00) for intrinsic conduction. Sites of greatest delay were concordant in all 7 patients during intrinsic conduction. During RV pacing, sites remained concordant or adjacent in all LBBB patients compared to intrinsic conduction CMR maps (correlation plot mean r = 0.94 (range: 0.85-1.00)), but did not agree with CMR in non-LBBB patients.Conclusion: Preoperative CMR-derived dyssynchrony maps have excellent correlation with intraoperative measurement of electrical delay. In those with classic LBBB, RV pacing did not affect the predictive utility of CMR in determining site of latest delay. These prospective data indicate CMR is a valid tool for preoperative, patient-specific planning of LV lead placement.

PO03-23

PATIENTS LESS RESPONSIVE TO BIVENTRICULAR PACING SHOW IMPROVEMENT WITH MULTISITE LEFT VENTRICULAR PACINGC. Aldo Rinaldi, MD, Wolfgang Kranig, MD, Christophe Leclercq, MD, PhD, Salem Kacet, MD, Tim Betts, MD, Pierre Bordachar, MD, Klaus-Juergen Gutleben, MD, Allen J. Keel, MS, Kyungmoo Ryu, PhD, Taraneh G. Farazi, PhD, Marcus Simon, BS and Tasneem Naqvi, MD. St. Thomas’s Hospital, London, United Kingdom, Schuechtermann-Klinik, Bad Rothenfelde, Germany, CHU Pontchaillou, Rennes, France, Hopital Cardiologique, Lille, France, John Radcliffe Hospital, Oxford, United Kingdom, University Hospital of Bordeaux, Bordeaux, France, Herz- und Diabeteszentrum NRW, Bad Oeynhausen, Germany, St. Jude Medical, Sylmar, CA, University of Southern California, Los Angeles, CAIntroduction: Multisite left ventricular pacing (MSLV) in a quadripolar LV lead (Quartet™, St. Jude Medical) improves acute dyssynchrony and contractility in CRT patients (pts). We tested the hypothesis that MSLV offers greater benefits to pts with dyssynchrony and weak contractility from simultaneous biventricular pacing (BiV).Methods: CRT pts (N=40) underwent echo assessment using tissue Doppler and radial strain during a pacing protocol comprising BiV and a set of 8 MSLV interventions. Echo analysis, including standard deviation of time to peak contraction of 12 LV segments (Ts-SD), early-to-late segment delay on strain (E-L), and global peak radial strain (GPRS) was performed by a core lab. For each pt, echo measurements during MSLV interventions were compared to those during BiV. For each echo measurement, we empirically determined a cutoff separating pts with greater or lesser BiV response, and the effect of the BEST MSLV was compared between the groups.Results: Compared to BiV, the mean Ts-SD was significantly lower for BEST MSLV (35.3±16.4 vs 50.2±19.1ms, p<0.001). The reduction in BEST MSLV Ts-SD compared to BiV was significantly greater for pts with BiV Ts-SD ≥ 50 ms (≥ 50ms: -29.8±19.6 vs <50ms: -3.52±15.5ms, p<0.001; Figure). The reduction in BEST MSLV E-L compared to BiV was significantly greater for pts with BiV E-L ≥ 120ms (≥ 120ms: -173±77 vs <120ms: -19±41ms, p<0.001). The mean increase in BEST MSLV GPRS compared to BiV was significantly greater for pts with BiV GPRS < 15% (≥ 15%: 3.4±6.7 vs <15%: 9.0±6.7%, p<0.001).Conclusion: MSLV from a single LV branch is effective in restoring synchrony and contractility in CRT pts, especially in pts with lower acute echo response to BiV.

pacing configuration in DDD mode and optimal VV biventricular pacing in VVI mode. If fusion was present and LVOT gradient remained >50 mmHg, AV-node ablation was performed. Results: Eight (66%) of the 12 patients evaluated showed fusion in the 12-lead ECG. The PR interval was 96±25 ms in the group of patients with fusion and 87±22 ms in those without. In the 5 patients with fusion in whom LVOT gradient remained >50 mmHg after device implantation, an AV-node ablation was carried out without complications. There was a progressive reduction in LVOT gradient from 101±11 mmHg at baseline to 82±33 mmHg with biventricular pacing (p=0.19) and to 57± 28 mmHg after AV-node ablation (p=0.049). There was a trend to increase the optimal AV delay after AV-node ablation from 112±30 ms to 154±25 ms (p=0.11).Conclusion: QRS fusion is a common finding in patients with HOMC undergoing biventricular pacing. In patients with fusion, AV-node ablation achieves a great additional LVOT gradient reduction.

PO03-22

MECHANICAL ACTIVATION MAPS DERIVED BY MAGNETIC RESONANCE AND THEIR CORRELATION TO INTRAOPERATIVE MAPS OF ELECTRICAL DELAY: IMPLICATIONS FOR INDIVIDUALIZED PREOPERATIVE LEFT VENTRICULAR LEAD IMPLANTATION.Michael S. Lloyd, MD, FHRS, Gregory Hartlage, MD, Michael Hoskins, MD, Shahriar Iravanian, MD, Jonathan Suever, MS and John Oshinski, PhD. Emory University, Atlanta, GA, Georgia Institute of Technology, Atlanta, GAIntroduction: One reason of clinical non-response to cardiac resynchronization (CRT) is failure to implant left ventricular (LV) leads at sites of late contraction. This site varies widely among the eligible population. Currently, there is no validated preoperative method to determine the site of latest mechanical delay and plan LV lead implantation. The purpose of this study was to compare preoperative LV mechanical activation patterns by cardiovascular magnetic resonance (CMR) to intraoperative LV electrical activation maps.Methods: Using a previously described novel imaging algorithm, CMR dyssynchrony maps were depicted via a 17- segment AHA model. Electrical delay maps were then generated intraoperatively by measuring delays at multiple sites within the coronary venous branches. Electrical delays were measured as peak-to-peak differences between the LV and right ventricular (RV) electrodes. Intraoperative measurements were then plotted against the corresponding EGM data to determine correlation. CMR and EGM data were considered concordant if in the same AHA segment, adjacent if within 1 segment, and remote if > 2 segments apart.


PO03-25

IMPROVEMENT IN ACUTE HEMODYNAMICS COMPARABLE BETWEEN SINGLE SITE PARA-HISIAN PACING AND BIVENTRICULAR PACINGAllan Shuros, MS, Félix Ayala-Paredes, MD, Rafael Barba-Pichardo, MD, Pablo Moriña-Vazquez, MD, Hung Fat Tse, MD, Jörg Neuzner, MD, Raymond Yee, MD, Stephen Hahn, PhD, Jiang Ding, PhD, Ljubomir Manola, PhD, Arjun Sharma, MD and Christian Butter, MD. Boston Scientific, Saint Paul, MN, University of Sherbrooke, Sherbrooke, QC, Canada, Hospital Juan Ramón Jiménez, Huelva, Spain, The University of Hong Kong, Queen Mary Hospital, Hong Kong, Hong Kong, Klinikum Kassel, Kassel, Germany, University of Western Ontario, London, ON, Canada, Boston Scientific, Brussels, Belgium, Immanuel Klinikum Bernau Herzzentrum Brandenburg, Bernau, GermanyIntroduction: Recent studies suggest pacing from the His bundle region can reactivate previously latent conduction fibers in patients with heart failure and conduction block, but unlike conventional biventricular (BiV) pacing used in cardiac resynchronization therapy (CRT), little is known of the acute hemodynamic effects of para-Hisian (PH) pacing in these patients. The purpose of this clinical study was to perform a paired acute hemodynamic comparison of PH pacing with BiV pacing in patients receiving a CRT system.Methods: Fourteen patients at six centers undergoing clinically indicated de novo CRT system implantation were studied. In addition to the standard right atrial, right ventricular and left ventricular (LV) leads, an electrophysiology catheter was positioned in the His bundle region and used for PH pacing. Capture of latent conduction fibers with PH pacing was assessed with 12-lead surface electrocardiograms. Left ventricular contractility was assessed by calculating the rate of rise (dP/dt) from signals collected with a high-fidelity pressure sensor catheter. Signals were recorded during randomized periods of BiV (simultaneous left ventricular epicardium and right ventricular apex or septum) and PH pacing. Paced beats were compared with a series of immediately preceding non-paced beats to calculate the percent change in dP/dt from baseline for each of the pacing configurations.Results: Capture of latent conduction fibers with PH pacing was evident in 7 of 14 total patients (50%). In these patients the mean QRS duration for intrinsic, BiV and PH paced beats was 174.6 ± 12.4 ms, 133.6 ± 13.1 ms, and 142.7 ± 23.5 ms, respectively (P=0.002). The mean percent improvement over baseline in LV dP/dt for BiV and PH paced beats was 20.6 ± 9.4 and 19.6 ± 5.5 (P=NS), respectively.Conclusion: Single site PH pacing reactivated latent conduction fibers in at least half of patients with CRT indications. In patients with ECG evidence of conduction correction during PH pacing, the hemodynamic response was as good as that achieved with BiV pacing. This suggests that PH pacing may be of value in the treatment of heart failure and conduction disease.

PO03-26

COMBINED LEFT BUNDLE BRANCH BLOCK AND QRS DURATION IS ASSOCIATED WITH SUPER-RESPONSE AND SURVIVAL AFTER CARDIAC RESYNCHRONIZATION THERAPYAmmar M. Killu, MBBS, Avishay Grupper, MD, Paul A. Friedman, MD, FHRS, David O. Hodge, MS, Samuel J. Asirvatham, MD, FHRS, Raul E. Espinosa, MD, Heather J. Wiste, BS, David Luria, MD, Yoni Buber, MD, Traci Webster, RN, Kelly L. Brooke, MS, Michael Glikson, MD and Yong-Mei Cha, MD, FHRS. Mayo Clinic, Rochester, MN, Leviev Heart Center, Tel Hashomer, Israel

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PRESSURE-VOLUME LOOP GUIDED LV-LEAD PLACEMENT IN CRT PATIENTS WITH SCAR TISSUEGerben J. De Roest, MD, LiNa Wu, MD, Carel C. De Cock, MD, PhD, Albert C. Van Rossum, MD, PhD and Cornelis P. Allaart, MD, PhD. VU University Medical Center, Amsterdam, NetherlandsIntroduction: Response to cardiac resynchronisation therapy (CRT) is hampered by extent and location of left ventricular (LV) scar tissue in ischemic end-stage heart failure patients. It is commonly advised to avoid scar tissue, while placing the LV lead. However, whether individual patients can be changed into responders using this strategy remains unclear. This study evaluates invasive pump function improvement during pacing at the location of scar tissue compared with viable myocardium.Methods: Thirty-five patients with end-stage heart failure based on ischemic cardiomyopathy and eligible for CRT were included. Cardiac magnetic resonance imaging with late contrast enhancement imaging was performed to assess scar tissue. Patients underwent invasive pressure-volume (PV) loop measurements to assess pump function during baseline and pacing at different sites of the LV. Pump function was quantified by Stroke Work (SW) which was defined as the surface of the PV-loop.Results: In the study population (28 (80%) men, NYHA class 2.8±0.4, ejection fraction (EF) 22±8%, QRS 148±21ms), baseline mean SW and dP/dtmax were 4.4±3.1 L mmHg and 854±205 mmHg/s, respectively. Both the extent and transmurality of scar tissue were inversely related to the acute increase in SW during pacing (respectively, R -0.53, P<0.001, R=-0.36, P=0.034). Stimulating postero-lateral (PL) scar tissue resulted in an acute deterioration of pump function ( SW -14±19%, P=0.028), whereas pacing at the location of viable tissue led to an increase in pump function (SW +59±51%, P<0.001). Switching from pacing at the location of scar tissue, irrespective of the scar location, to viable tissue showed a significant increase in SW from -4±21% to +18±37% (P=0.023).Conclusion: The extent and transmurality of scar tissue are reversely related to pump function improvement during CRT. Pacing at the location of (transmural) scar tissue will generally deteriorate LV pump function. Placing the LV lead over viable myocardium significantly improves pump function as compared with pacing at the location of scar tissue in patients with ischemic cardiomyopathy.


the care pathway and treatment of unexplained syncope, including 570 patients. In this analysis, a UK micro-costing study quantified the economic burden of investigation and showed the actual “bottom-up” costs of each of 17 predefined diagnostic tests. After the ILR implant patients were followed until a symptomatic event with a device-captured ECG or for at least one year.Results: The median number of tests before ILR implant was 13 (IQ range 9 - 20). The minimum number was 0 and the maximum was 203. Among the top 25% patients, the median number of tests was 27 (IQ range 22-36). Based on the tag-on micro-costing study, the mean cost per patient was £1,613 ($2,597 - CI £1,552 - £1,674), median £1,113 ($1,793 - IQ range £568 - £2,246), but it could reach £7,417 ($11,942). The cost of a patient receiving every type of investigation once, including ECG, Holter, blood pressure provocation, TILT test, neurological evaluation, coronary angiography, MRI, CT, invasive EP testing etc., would have been £4,007 ($6,452). In 12% of the PICTURE population the pre-implant investigation was consistent with the initial evaluation according to the current ESC guidelines, and in those the cost per patient was £710 ($1,143). In contrast, the mean cost per patient among the top 25% patients was £3837 ($6,178 - 95% CI £3,716 - £3,958).Conclusion: Most of the PICTURE patients were investigated more than suggested in guidelines before an ILR implant. The costs were highly significant and the mean cost per patient was about twice that of the recommended investigations, and in the top quartile several times higher. Identification of resource intensive patients can be an algorithm for faster identification of ILR candidates at a significantly lower cost.

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INTRACARDIAC ECHOCARDIOGRAPHY ASSISTED PLACEMENT OF A THIN LUMENLESS LEFT VENTRICULAR ENDOCARDIAL LEAD FOR CARDIAC RESYNCHRONIZATION THERAPY USING A SNARE TECHNIQUEAlaa A. Shalaby, MD, Genevieve Brumberg, MD and John Nosbisch, RN. Pittsburgh VA Healthcare System, Div of Cardiology, Pittsburgh, PA, University of Pittsburgh, Pittsburgh, PAIntroduction: Left ventricular endocardial (LVE) pacing may be an alternative to deliver cardiac resynchronization therapy (CRT) when coronary sinus branch placement fails. We describe our early experience using a combined femoral and left subclavian approach.Methods: All patients were chronically anticoagulated for pre-existing clinical reasons. Implants were performed with therapeutic INR levels. Through left subclavian venous access a deflectable sheath (DS) was passed to the right atrium. Intravenous heparin was given to achieve an activated clotting time >250 secs. Under intracardiac echocardiographic monitoring (ICE; Boston Scientific, USA), transeptal puncture was performed using a femoral sheath. The septal puncture point was dilated by repeat passage of the sheath which was then retracted to the right atrium where it was snared through the superior sheath. The femoral sheath was passed back to the left atrium through the dilated puncture site along with the DS. The DS was then freed from the femoral sheath which was again withdrawn to the right atrium. The DS was directed to a posterior location in the LV and a 4 Fr lumenless lead (Select Secure, Medtronic USA) was fixed to the endocardium. Under ICE visualization, the DS was pulled back into the right atrium slit and removed.Results: Five patients underwent LVE lead placement. LVE lead placement in a posterior position was successful, well tolerated and with no complication in all cases. Thresholds remained stable over time (Table).

Introduction: Cardiac resynchronization therapy (CRT) improves heart failure (HF) symptoms and survival. New guidelines classify CRT indications using the presence of LBBB and QRS duration ≥150ms, in addition to LVEF and NYHA class. We sought to determine the effect of these parameters on response and survival to CRT.Methods: In 728 patients who received CRT across two centers, the change in LVEF pre- and post-CRT was determined. Patients were grouped as non-, moderate- or super-responders to CRT, defined as an absolute change in LVEF of ≤5%, 6-15% and >15%, respectively. Difference in QRS duration and morphology were compared between groups categorized as non-LBBB/QRS <150ms, non-LBBB/QRS ≥150ms, LBBB/QRS <150ms and LBBB/ QRS ≥150ms.Results: There were 419 (57.6%) non-, 195 (26.8%) moderate- and 114 (15.7%) super-responders. Super-responders were more likely to be female, have DCM, QRS duration >150ms and lower LVEF and PASP than non-responders. They tended to have more LBBB than non-responders (P=0.06). In addition, super-responders were more likely to have combined LBBB/QRS duration ≥150ms than the non- and moderate-responder groups (49% vs. 34% vs. 34%, respectively, P≤0.01).There was a significant difference in survival between super- compared to moderate- and non-responders: 89% vs. 79% and 70% at 4 years (P=0.02 and P<0.01, respectively). Furthermore, Kaplan-Meier estimate (figure) revealed greater survival in those with LBBB/QRS ≥150ms compared to non-LBBB/QRS≥150ms (P<0.01) and LBBB/QRS <150ms (P=0.04).Conclusion: The presence of combined LBBB and QRS duration ≥150ms is associated with an increased incidence of super-response to CRT and, therefore, survival.

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A MICRO-COSTING ANALYSIS OF DIAGNOSTIC TESTS FOR UNEXPLAINED SYNCOPE - ARE WE DOING TOO MUCH?Nils G. Edvardsson, MD, PhD, Stelios Tsintzos, MD, Claudio Garutti, PhD, Guido Rieger, MD and Nick Linker, MD. Sahlgrenska Academy at Sahlgrenska University Hospital, Göteborg, Sweden, Medtronic Bakken Research Center, Maastricht, Netherlands, James Cook University Hospital, Middleborough, United KingdomIntroduction: Transient Loss of Consciousness and Syncope are among the Top-20 reasons for hospital admission in the UK. Claims data analyses demonstrated these episodes to be increasing. We analysed the costs of the clinical investigations commonly performed for unexplained syncope and measured their volume in a real-world setting, before a decision to implant an implantable loop recorder (ILR) was made.Methods: PICTURE was a prospective, observational registry on


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LEAD PERFORATIONS WITH MEDTRONIC 5086MRI LEADKenneth W. McBride, MD, Jessica Gamwell, PA and Theodore Takata, MD. Consultants in Cardiology, Forth Worth, TXIntroduction: The Medtronic Revo MRI SureScan system was the first FDA approved system, allowing those requiring permanent pacing therapy to safely undergo magnetic resonance imaging. In addition to an MRI compatible generator, the system includes an MRI safe lead (5086MRI), which uses a modified filar design to minimize lead tip heating, inadvertent cardiac stimulation and MRI induced electrical interference. Initial Medtronic clinical reports showed equivalent complication rates with MRI lead implants as compared to other active fixation leads; however, a study presented at the 2012 Heart Rhythm Society noted an increased rate of postoperative lead perforations and lead repositioning. Within our practice, we have seen similar results, with unexpected increases in those same complications. This study aims to compare postoperative lead perforations between the Medtronic 5086MRI leads and all other active fixation leads placed during the same time frame within our practice.Methods: A retrospective analysis was performed, looking at Medtronic 5086MRI lead placement postoperative lead perforations as compared to all similar active fixation lead complications (including Medtronic models 6947, 3830, 5076, 4076, 6935) over an 18 month period of time within one practice. Lead choice was at the physicians’ discretion.Results: 118 Medtronic 5086MRI leads and 623 Medtronic non-MRI active fixation leads were placed during the study time frame by 3 experienced physicians. There were 3 lead perforations (2.5%) in the MRI group and 1 suspected lead perforation (0.16%) in the non-MRI group (p value 0.014, Fischer’s exact test). All MRI lead complications required post operative lead repositioning with one case requiring surgical repair of perforation. The non-MRI lead complication involved a suspected subacute lead perforation with pericardial effusion, requiring pericardial drainage without lead repositioning.Conclusion: There appears to be an increased rate of postoperative lead perforations in the 5086MRI leads. It is unclear if this is due to the lead design or its current placement techniques, possibly prompting the need for further investigation.

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OVER ONE THOUSAND LASER LEAD EXTRACTION: SINGLE CENTER EXPERIENCEYoji Okamoto, MD, Christian S. Balabanoff Acosta, MD, Juan Garisto, MD and Roger Carrillo, MD, FHRS. University of Miami, Miami, FLIntroduction: There are an increasing number of patients with cardiac implantable electrical devices (CIED). Over the last decades, CIED infection and lead malfunction has been increasing. There are limited reports from high volume single center laser lead extraction.Methods: We examined consecutive 955 lead extraction procedures at single tertiary referral center from January 2004 and October 2012. Clinical characteristics, leads details, extraction method, indications and outcomes were analyzed. We used denitions outlined in the HRS 2009 Lead Extraction Expert Consensus.Results: Among 955 patients(Male 74%, Female 26%), Age 68±15 years, EF 36±15%, NYHA 2.3±1.1, BMI 27.6±7.0. Significant comorbidities were CAD 60%, DM 42%, and Hemodialysis 11.7%. Devices extracted were PM 37.8%, ICD 41.4%, CRT 20.5%. Indication were infection 65.6%, malfunction

Conclusion: Stable LVE lead placement is feasible using the method described. ICE was instrumental in securing a safe transeptal puncture and sheath removal from the left side prior to its splitting, without excessive fluoroscopy.

Age (yrs) BMI EF

(%)LVEDD (mm)

Procedure Time (mins)

Flouroscopy Time (mins)

Follow up (months)

Pacing Threshold ([email protected] msec)

Impedance (ohms)

68 30.3 30 60 380 32.5 18.5 0.4 69672 29.63 20 66 100 9.6 14.5 0.5 65065 31.96 30 57 137 23.5 14.3 0.5 77963 36.8 20 76 226 41.6 0.5 0.5 47263 35.04 25 60 217 33 5.8 0.25 456

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QUADRIPOLAR LEFT VENTRICULAR LEADS YIELD LOWER CAPTURE THRESHOLDS WITH EXPECTED INCREASE IN BATTERY LONGEVITYHarish Manyam, MD, Ashish A. Bhimani, MD, Shervin A. Sadrpour, MD, Samer A. De Oliveira, MD, Robert N. Goldstein, MD, FHRS, Ivan Cakulev, MD, Jayakumar Sahadevan, MD, Mauricio Hong, MD, Anselma Intini, MD, Mauricio Arruda, MD and Judith Mackall, MD. Univeristy Hospitals Case Medical Center, Cleveland, OHIntroduction: The introduction of the quadripolar left ventricular lead has provided CRT implanters with additional pacing configurations using a single lead. Benefits include the ability to avoid phrenic nerve stimulation and to deliver pacing at more basal sites without compromising secure lead positioning. In addition, the configuration with the lowest pacing threshold is often selected. We hypothesized that this would result in increased battery longevity.Methods: We performed a single-center, retrospective analysis of de novo CRT-D implants from 2011 to 2012. The LV lead parameters were compared between the quadripolar (St. Jude Medical Quartet LV lead) and non-quadripolar (bipolar or unipolar leads from any company) groups. The patients with high LV lead capture thresholds (>2.0 V at 0.5 msec) were also identified and compared separately. Battery longevity for each case was determined from industry estimation using the final LV parameters and presumed 100% dual chamber biventricular pacing. Chi-square and unpaired t-tests were used for statistical analysis of proportions and means, respectively.Results: Ninety consecutive patients who underwent de novo CRT-D implants were included in the analysis. Eighteen patients received a quadripolar LV lead and 72 patients received either a unipolar or bipolar LV lead. The mean capture threshold for quadripolar LV leads was significantly lower than that of other LV leads, 0.82 ± 0.32 V vs. 1.25 ± 0.78 V (p=0.024), with no significant difference in pulse width or impedance values. There were no high capture thresholds in the quadripolar group while 13.9% (10/72) of patients in the non-quadripolar lead group had high thresholds (p=0.047). The estimated battery longevity was 92.3 ± 1.4 in the quadripolar group vs. 90.0 ± 3.6 months in the non-quadripolar group (p=0.008). Furthermore, in patients with high LV thresholds (mean estimated battery longevity of 84.3 ± 5.2 months), a quadripolar lead would have resulted in an improvement of battery longevity of 8.0 ± 5.2 months (p<0.001).Conclusion: In conclusion, the use of quadripolar LV leads resulted in lower mean LV capture thresholds and a significant improvement in estimated battery life.


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POCKET SCAR PREDICTS EXTRACTION DIFFICULTYMelanie Maytin, MD, Roy M. John, MD, PhD and Laurence M. Epstein, MD. Brigham and Women’s Hospital, Boston, MAIntroduction: The challenges and risks of transvenous lead extraction (TLE) of cardiovascular electronic implantable devices (CIED) are principally related to the body’s foreign body response to endovascular leads. Despite our understanding of the histopathologic changes following endovascular lead implantation, predictors of severe endovascular scar formation have not been clearly identified. We hypothesize that the severity of pocket scar may help predict endovascular scar and hence, TLE difficulty.Methods: We performed a prospective analysis of consecutive patients undergoing lead extraction. Patient and procedural characteristics, classification of pocket scar severity (scale: mild, moderate, severe), extraction time and number and use of extraction sheath (ES) assistance are reported. TLE difficulty was defined as the combined endpoint of the need for ≥2 sheaths, and/or extraction time > 75th percentile. Procedural characteristics and outcomes were compared using t-tests for continuous data and Fisher’s Exact Test for dichotomous/ordinal data. Logistic regression analysis was utilized to test the adjusted association between pocket scar and the combined endpoint.Results: Between Nov 2010-Feb 2012, 146 patients underwent TLE with assessment of pocket scar. The cohort was 63% male with mean age 62±16 yrs. Average implant duration was 84±53 months. Indications for TLE included: infection 35%, malfunction 30%, upgrade 8% and other 27%. ES assistance was employed in 79% of cases. Average procedural time was 4.1±9.1 min with an average 1.8±0.9 leads removed/procedure. Major complication rate was 1.39%. Each incremental increase in pocket scar severity was associated with a 2-fold increase in TLE difficulty (OR 2.03 [1.005, 4.110]) after adjusting for age, gender, implant duration, number of leads removed and TLE indication.Conclusion: The severity of scar in the device pocket correlates with multiple ES use and long extraction times and may help predict TLE difficulty.

30.0%. An average of 2.1±0.9 leads were extracted per patient, totaling 1968 leads (PM lead 67.3%, ICD lead 31.3%. All patients underwent laser lead extractions procedures. In patients with multiple leads, manual traction was employed in 24.6% (n=484) of the leads, and laser sheath were used in 75.4% (n=1484).14Fr. Laser sheath size was most commonly used (70.2%). Procedural success rate was 99.9%. There were 68 laser related adverse events (major 20, minor 48, including 3 deaths). Patients on hemodialysis were noted to have longer hospital stay in regardless of the indication for extraction. (Infection; 22.3±1.3 vs 16.1±0.5, p=<0.0001, Malfunction; 14.5±2.5 vs 6.8±0.6, p=0.003).Conclusion: Laser extraction is a safe procedure with high clinical success rate.

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MULTICENTER EXTRACTION EXPERIENCE WITH CHRONIC MEDTRONIC LV LEADSRobert A. Sorrentino, MD, FHRS, Stuart W. Adler, MD, Derek V. Exner, MD, MPH, FHRS, Andrew D. Merliss, MD, Serge M. Tobias, MD, Clayton T. Miller, MBA, Pei Li, PhD and George H. Crossley, MD, FHRS. Medical College of Georgia, Augusta, GA, HealthEast Heart Care, St. Paul, MN, Libin Cardiovascular Institute, Calgary, AB, Canada, Bryan Heart, Lincoln, NE, Long Beach Memorial, Long Beach, CA, Medtronic Inc., Minneapolis, MN, St. Thomas Heart University of Tennessee, Nashville, TNIntroduction: Data on chronic LV lead extraction (LVX) is limited. The StarFix Extraction study explores the removability of Medtronic LV leads. The study prospectively enrolled patients (pts) at 29 experienced extraction centers.Methods: Pts with LV leads implanted for ≥181 days requiring LV lead extraction (LVX) were included. Extraction success was defined using the 2009 HRS Consensus on lead extraction. Follow-up was for one month.Results: A total of 138 LVX procedures had been adjudicated. Pts were 75% male, median age 68 years, 51% had ischemic cardiomyopathy, 59% coronary artery disease and 41% diabetes. LV leads were implanted for a median of 4.05 years (range 0.5 -9.7). Most LVX were due to infection (48%). Extraction tools included laser sheaths with locking stylets [LS] (51%), manual sheaths with LS (5%), LS alone (17%) or manual traction alone (21%). Overall LVX success was 97% (figure) with 4 failures (2 model 4193, 2 model 4195). In 3 of the failed LVX pts, the only tool used was a standard stylet or LS. Three LV leads were capped. The fourth failure prompted surgical removal of all leads. Major complication rates were similar for all models and included cardiac tamponade (1), pulmonary embolism (1) and mediastinal hemorrhage (1). None of 3 reported deaths were related to the LVX procedure.Conclusion: This is one of the largest studies to date on Medtronic LVX. Experienced extractors successfully removed 97% of LV leads. We observed that the majority of lead models 4193 and 4195 required mechanical extraction tools. In this series the observed major complication rate for extraction of chronic LV leads is similar to that reported for non-LV leads.


Introduction: ICDs have increasingly been used not only to provide life-saving therapy, but to collect diagnostics, such as AF burden, to monitor patients’ heart disease. ICDs can send wireless alerts through remote monitors once a programmable burden has been reached. The objective of this study was to determine the impact of AF monitoring in patients with no history of AF.Methods: This is a retrospective evaluation of Medtronic ICDs implanted from 1/1/05-6/30/12 that were followed by Pee Dee Cardiology in Florence, SC. Patients were excluded if they had documented AF or were already on anticoagulants before device implant or if they did not have an atrial lead. Based on method of follow-up, patients were placed in three groups: (1) No CareLink, (2) CareLink without wireless AF alert, (3) CareLink with wireless AF alert. Information was collected through EMR, Paceart, and in-office/remote checks. CareLink patients were checked in-office yearly and remotely every 3 months. Patients without CareLink were checked in-office every 3 months. The primary endpoints are time from initial AF onset until clinic awareness and treatment.Results: A total of 22 (4.8%) new onset AF patients, with an average CHADS2 score of 2.86 ± 1.01, were identified out of 455 patients.

Days to Clinic Awareness

Days to Treatment*

Group 1 (No CareLink) n=4 60 63Group 2 (CareLink without Wireless AF Alert) n=11 44 46Group 3 (CareLink with Wireless Alert for 12 hour AF Burden) n=7 8 9

* Treatment summary: 16 patients placed on anticoagulation4 patients had beta blocker changes due to AF with RVR2 patients had no medication change (Falls risk)

Using an ANOVA, Group 3 had a statistically significant decrease in days to clinic awareness (p=0.0039) and days to treatment (p=0.0075).Conclusion: Remote monitoring has become common with 67% of high power devices implanted in the U.S. enrolled in CareLink. Wireless alerts are not utilized nearly as frequently, with only 21% of wireless AF burden alerts enabled. Physicians should consider programming the wireless AF burden alert on for patients with no history of AF.

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PROSPECTIVE EVALUATION OF CINEFLUOROSCOPY AND CHEST RADIOGRAPHY FOR RIATA SCREENING: IMPLICATIONS FOR FUTURE LEAD ASSESSMENTPeem Lorvidhaya, MD, Ivan Mendoza, MD, Sharmila Sehli, MD, Michael Atalay, MD, PhD and Michael H. Kim, MD, FHRS. Alpert Medical School of Brown University, Providence, RIIntroduction: Lead insulation defects with externalization of the high voltage conductors exist in Riata defibrillator leads. Recent data show that cinefluoroscopy is effective in the diagnosis of such defects. Prospective evaluation of alternative screening options such as standard chest radiography (CXR), which has been recommended by the FDA, is not well described.Methods: Patients (pts) with Riata leads underwent cinefluoroscopy (AP, RAO 45, and LAO 45 degrees), PA/lateral CXR, and device interrogation on the same day. Leads were classified as abnormal (clear cable separation), borderline, or normal by independent and blinded evaluation of cinefluoroscopy and CXR. CXR evaluation was done in two ways: 1) routine CXR read by daily staff radiologists for lead screening and 2) CXR evaluation by a radiologist informed about the lead defect.Results: One hundred and two pts were evaluated at our institution. Cinefluoroscopy showed abnormal externalized

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LEFT VENTRICULAR PACING FROM A SITE OF LATE ELECTRICAL ACTIVATION IMPROVES ACUTE HEMODYNAMIC RESPONSE TO BIVENTRICULAR PACING IN PATIENTS WITH CONDUCTION DELAY GREATER THAN TEN MILLISECONDS IN A QUADRIPOLAR LEFT VENTRICULAR LEADCarlo Pappone, MD, PhD, Zarko Calovic, MD, Amarild Cuko, MD, Luke C. McSpadden, PhD, Kyungmoo Ryu, PhD, Massimo Saviano, MD, Mario Baldi, MD, Alessia Pappone, MD, Cristiano Ciaccio, MD, Luigi Giannelli, MD, Andrea Petretta, MD, Bogdan Ionescu, MD, Raffaele Vitale, MD, Gabriele Vicedomini, MD and Vincenzo Santinelli, MD. Maria Cecilia Hospital, GVM Care & Research, Cotignola, Italy, St. Jude Medical, Sylmar, CAIntroduction: Patients (pts) undergoing cardiac resynchronization therapy (CRT) may benefit from an individualized left ventricular pacing (LVP) site. We hypothesized that selecting an LVP site based on electrical activation time during right ventricular pacing (RVP) could improve acute hemodynamic response.Methods: Forty-one pts receiving a CRT implant (Unify Quadra MP™ or Quadra Assura MP™ CRT-D and Quartet™ LV lead, St. Jude Medical) underwent LV hemodynamic assessment using a pressure-volume loop system (Inca, CD Leycom). LV pressure was recorded during biventricular pacing with LVP at each of two LV sites (one distal, one proximal) in a quadripolar LV lead. Each pacing intervention was performed twice in a randomized order with RVP (BASELINE) repeated after each intervention. Electrical activation time at both LV sites was computed during RVP using intracardiac electrograms available on the device programmer (Fig. A).Results: Pressure recordings were obtained in 37/41 pts. The mean difference in RVP induced electrical conduction delay between the early activated site and the late activated site along the quadripolar LV lead (Δdelay) was 11.8±8.9 ms (range: 0-33 ms). There was no difference in dP/dtMax relative to BASELINE in pts with Δdelay <10ms (12.3±8.8% vs. 11.6±8.6%, p = 0.3, Fig. B), however, pts with Δdelay >10ms received significant dP/dtMax benefit from pacing at the site of late activation (10.7±9.8% vs. 13.5±9.5%, p = 0.017).Conclusion: Targeting the site of late activation for LVP significantly improves acute hemodynamic response to CRT and offers a simple way to optimize the LVP site with multipolar LV leads. Additional studies may help determine the overall clinical utility of these findings.

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UTILIZING REMOTE MONITORING AND WIRELESS ALERTS FOR IDENTIFICATION OF NEW ONSET ATRIAL FIBRILLATION IN DEFIBRILLATOR PATIENTSRajesh Malik, MD, Christina Parks, Brendon Malik, MD, Bobby Malik, Dennis Cattel, BS and Jason Sims, PharmD. Pee Dee Cardiology Associates, Florence, SC, University of South Florida, Tampa, FL, Wofford College, Spartanburg, SC, Medtronic, Minneapolis, MN


point <0.001). At multivariate analysis, factors associated with the endpoints were: presence of AF, use of loop-diuretics, NYHA class, QRS duration (only for combined event) and CHA2DS2-VASc class of risk (for HF-hospitalization, H.R. 3-4 vs 1-2 1.94; 95% C.I. 1.08-3.46; H.R. 5-8 vs 1-2 2.42; 95% C.I. 1.33-4.39; for combined event, H.R. 3-4 vs 1-2 1.58; 95% C.I. 0.99-2.52; H.R. 5-8 vs 1-2 2.12; 95% C.I. 1.31-3.42).Conclusion: In CRT-D patients pre-implant CHA2DS2-VASc score is able to predict the occurrence of major clinical events at 6-year follow-up.

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INCIDENCE OF CARDIAC ARRHYTHMIAS IN INTENSIVE-CARE-UNIT PATIENTS DOES NOT INCREASE DURING HEMODIALYSISMihail G. Chelu, MD, PhD, Yahya Ibrahim, MD, Navneet Singh, MD, Farah Shanoon, MD, Mohammad Saeed, MD and Mehdi Razavi, MD. Texas Heart Institute at St. Luke’s Episcopal Hospital, Houston, TXIntroduction: Patients undergoing chronic hemodialysis (HD) have numerous comorbidities, such as diabetes, anemia, hyperparathyroidism, and hypertension, that promote structural heart disease. Also, fluid overload and metabolic abnormalities_including metabolic acidosis, dyskalemia, and dysmagnesemia_increase the risk of significant arrhythmias and sudden cardiac death. The incidence of cardiac arrhythmias in the peri-HD period is unknown. We hypothesized that in intensive care unit (ICU) patients, the incidence of this complication increases during and shortly after HD.Methods: The study population comprised 101 randomly selected ICU patients (age 57±14 yr; range 18-80 yr) undergoing HD. They had no preexisting history of sustained cardiac arrhythmias, accessory pathways, cardiopulmonary resuscitation, or implantable cardiac rhythm devices. Telemetry was used to monitor arrhythmic events before, during, and after HD (3.6±0.7 hr each); a blinded review of the data was performed by an independent, board-certified electrophysiologist. The following cardiac arrhythmias were identified: paroxysmal atrial tachycardia, atrial fibrillation, nonsustained ventricular tachycardia, ventricular bigeminy, and accelerated idioventricular rhythm. The incidences of arrhythmias before, during, and after HD were compared by using a 2-tailed Fisher�s exact test. Data collected retrospectively from medical records included cardiac medical and surgical history, renal medical history, electrolyte levels, and details of HD fluid removal.Results: The creatinine and potassium levels were 5.5±4.6 mg/dl and 4.2±0.7 mEq/L, respectively. On average, 2.2±1.2 L of fluid was removed. The incidence of arrhythmias before, during, and after HD was 2.9%, 3.9%, and 4.9%, respectively; the differences in these percentages were nonsignificant.Conclusion: Fluid removal and electrolyte shifts during HD do not affect the incidence of cardiac arrhythmias in ICU patients. This finding may reflect improved HD practices, close ICU patient monitoring, and nephrologist supervision of procedures.

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ANALYSIS OF VENTRICULAR ARRHYTHMIA EPISODES AND ANTI-TACHYCARDIA PACING THERAPIES IN IMPLANTABLE CARDIOVERTER-DEFIBRILLATORSJohannes Siebermair, MD, Eimo Martens, MD, Franziska Schuessler, MD, Reza Wakili, MD, Heidi L. Estner, MD, PhD and Stefan Kääb, MD, PhD. Medizinische Klinik I, Munich, GermanyIntroduction: ICD therapy is delivered to treat life-threatening VF episodes by applying defibrillation shocks. ICDs do not

conductors in 33 pts (32%) and borderline findings in 6 pts (6%). Twenty-five of 33 pts (76%) who had abnormal cinefluoroscopic findings had abnormal CXR findings on review by the informed radiologist. All 25 pts with abnormal CXR had abnormal findings on cinefluoroscopy (specificity 100 %). Five out of 102 pts (5%) had abnormal electrical findings on device interrogation; all 5 of these pts had both abnormal cinefluoroscopy and CXR. Daily staff radiologists without direct education other than prompts for lead screening detected CXR abnormalities in only 8 out of 102 (8%) cases.Conclusion: Cinefluoroscopy appears to be better than standard chest radiography for the detection of Riata cable extrusion. Interpretation of standard PA/lateral CXR by a radiologist with training in lead defects correlates highly with cinefluoroscopy, the current gold standard, with very high specificity. Depending on available resources for screening especially in underserved areas, CXR may be a reasonable alternative to cinefluoroscopy. CXR can also be a potential first step in the process, with negative CXR proceeding to cinefluoroscopy. Multidisciplinary collaboration across specialties (radiology and electrophysiology) can lead to improved diagnostic capability and thus the potential for enhanced quality of care.

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CHA2DS2-VASC SCORE TO PREDICT LONG-TERM PROGNOSIS IN PATIENTS CANDIDATE TO CARDIAC RESYNCHRONIZATION THERAPYAlessandro Paoletti Perini, MD, Simone Bartolini, MD, Giuseppe Ricciardi, MD, Paolo Pieragnoli, MD, Alice Rossi, MD, Stefania Sacchi, MD, Giuseppe Vergaro, MD, Alessandro Valleggi, MD, Federica Michelotti, MD, Giulio Boggian, MD, Biagio Sassone, MD, Giosuè Mascioli, MD, Michele Emdin, PhD and Luigi Padeletti, MD. Università degli Studi di Firenze, Firenze, Italy, Fondazione Toscana Gabriele Monasterio, Pisa, Italy, Istituto Humanitas Cliniche Gavazzeni, Firenze, Italy, UO di Cardiologia Ospedale di Bentivoglio, Bentivoglio (BO), ItalyIntroduction: CHA2DS2-VASc score is the most accurate instrument to assess the risk of stroke in patients affected by AF. It was recently demonstrated that it is able to predict hospitalizations for cardiovascular causes in patients affected by AF. We aimed at evaluating if CHA2DS2-VASc score is able to predict long-term clinical outcome (hospitalization for HF and combined event of HF hospitalization and death for any cause, whichever comes first) in a population of HF patients candidates to CRT-D.Methods: we calculated the pre-implant CHA2DS2-VASc score of 559 consecutive HF patients who underwent the implant of CRT-D according to International Guidelines. Patients were classified in 3 pre-specified classes of risk according to the CHA2DS2-VASc score: low (score 1-2), medium (score 3-4) and high risk (score 5-8). Patients were clinically followed every 6 months.Results: Out of 559 patients (mean age 70±9 years, female 24.9%, mean QRS 157±20 msec, mean FE 26.9±5.5%, mean NYHA class 2.8±0.6, history of AF 24.5%), 108 (19.3%) were at low risk, 259 (46.3%) at medium risk and 192 (34.4%) at high-risk. Median follow-up was 30 months (25°-75° percentile 15-52 months); during the whole follow-up, 143 patients (25.4%) had at least one hospitalization for HF and 110 (19.5%) died. Median time to first HF-hospitalization was 25 months, to the combined end-point was 24 months. The event-free survival analysis, by the Kaplan-Meier method, showed a significant difference for both the end-points according to the patients� baseline risk both for the original score (Log-Rank test for HF 0.002, Log-Rank test for combined end-point <0.001) and after reclassification (Log-Rank test for HF <0.001, Log-Rank test for combined end-


in 14 pts, and replacement plus lead revision or upgrade in 9 pts. Warfarin was continued in 195 pts undergoing device implantation (age 60 + 14.4 yrs, 54F and 141M). The procedure was a new implant in 122 pts, replacement in 33 pts, and replacement plus lead revision or upgrade in 40 pts. Bleeding complications occurred in 1 of 48 pts (2.1%) on dabigatran (no hematomas and 1 pericardial effusion) and 9 of 195 pts (4.6%) on warfarin (9 hematomas and no pericardial effusions), p=0.69.Conclusion: CIED implantation can be performed safely with uninterrupted OAC with either dabigatran or warfarin. The risk of bleeding complications with device implantation is similar with both agents.Bleeding Complications with CIED Implantation in Patients Anticoagulated with Dabigitran vs Warfarin

Uninterrupted Dabigatran

Uninterrupted Warfarin p-Value

Number of Patients 48 195Age (years), mean+ SD 66 + 12.4 60 + 14.4 0.009Male: Female 35:13 141:54 1.0First Implant, n (%) 25 (52) 122 (63) 0.19PG Replacement, n (%) 14 (29) 33 (17) 0.07Lead Revision / Upgrade, n (%) 9 (19) 40 (21) 1.0Bleeding Complications, n (%) 1 (2.1) 9 (4.6) 0.69

PO03-41

DIVERGENT CHANGES IN LEFT VENTRICULAR EPICARDIAL ACTION POTENTIAL DURATION IN RESPONDERS AND NON-RESPONDERS TO CARDIAC RESYNCHRONISATION THERAPYZhong Chen, MRCP, Ben Hanson, PhD, Manav Sohal, MRCP, Eva Sammut, MRCP, Nick Child, MRCP, Anoop Shetty, MD, Julian Bostock, BSc, Matthew Wright, PhD, MRCP, Michael Cooklin, MD, FRCP, Mark O’Neill, PhD, MRCP, Jaswinder Gill, MD, FRCP, Gerald Carr-White, MD, FRCP, C. Aldo. Rinaldi, MD, FRCP and Peter Taggart, DSc. King College London, London, United Kingdom, University College London, London, United Kingdom, University College London Hospital, London, United KingdomIntroduction: A consistent feature of electrophysiological remodelling in heart failure is ventricular action potential duration (APD) prolongation. However, the effect of reverse remodelling on APD during cardiac resynchronisation therapy (CRT) has not been determined in these patients. We hypothesised (1) CRT may alter APD and (2) that the effect of CRT on APD may be different in patients who exhibit a good haemodynamic response to CRT compared to those with a poor response.Methods: LV activation recovery intervals (ARI), as a surrogate for action potential duration, were measured from the LV epicardium in thirteen patients at day 0, 6 weeks and 6 months following CRT implant. Responders to CRT were defined as those demonstrating a ≥15% reduction in LV end-systolic volume at 6 months.Results: The responder group had a significant reduction in LVARI (mean: -13ms±12ms; median: -16ms, IQR -2ms to -19ms) during RV pacing at 6 months (p<0.05). Conversely the non-responders showed a significant increase in ARI (mean: +22ms±16; median: 17ms, IQR 8ms to 35ms) (p<0.05). See Figure 1.Conclusion: In patients with heart failure left ventricular epicardial APD (ARI) altered during CRT. The effect on APD was opposite in patients showing a good haemodynamic response compared to non-responders. The findings may be relevant to the persistent high incidence of arrhythmias in some patients with CRT.

only provide shock therapy but also antitachycardia overdrive stimulation (ATP). Studies have demonstrated that ATP could terminate >80% of VT and fast VT (fVT) episodes up to 220/min. “Real-life” data of large cohorts regarding frequency and effectiveness of ATP therapy are missing. The objective of this analysis was a) to evaluate the frequency of ATP in a large cohort of ICD patients, and b) to verify the success rate of ATP to avoid shock therapy.Methods: Retrospective analysis of 9821 device interrogations (977 ICDs, thereof 520 (53.2%) single-chamber and 457 (46.8%) dual-chamber devices) from 1998 to 2012 was performed.Results: In total 4 125 ventricular arrhythmia episodes occurred (736 VF, 352 fVT and 3037 VT episodes). Programming analysis revealed an active ATP therapy in 880/977 (90.1%) devices. In total 3331/4125 (80.2%) of episodes were treated by ATP therapy with an overall ATP success rate of 97%.The VF detection zone (mean 283,77ms ± 29,49ms) was programmed ON in 947/977 (97%) devices with an active ATP therapy in 831/947 (87.8%). 22% of episodes in this zone were treated by ATP with a success rate of 69%. In 559/977 (57.2%) of devices with fVT detection ON (mean 344,42ms ± 34,18 ms), ATP therapy ON was found in 556/559 (99.5%) devices. In this therapy zone 85% of episodes were treated by an ATP (success rate of 93%). In 813/977 (83.2%) of devices with active VT detection (372,91ms ± 47,24ms), ATP therapy was provided in 774/813 (95.2%) devices and a success rate of 99%. Shorter ATP coupling intervals were significantly correlated with higher ATP success rates (85±4.1% vs 87.3±3.3%, p<0.001). Ventricular ATP with arrhythmia acceleration and subsequent shock delivery was found in 96/4125 (2.3%) episodes.Conclusion: ATP therapy is highly effective in terminating ventricular arrhythmia, especially in the VT and fVT zone. Consideration of at least one ATP sequence in the VF zone should be given to the high success rate of almost 70% in this zone. ATP therapy acceleration and subsequent shock therapy was rare.

PO03-40

PACEMAKER AND ICD IMPLANTATION WITH UNINTERRUPTED DABIGATRAN COMPARISON TO UNINTERRUPTED WARFARINJohn M. Jennings, MD, Anita Kelly, BS, Alicia Gunter, Hugh T. McElderry, MD, Robert Robichaux, MD, Harish Doppalapudi, MD, Jose Osorio, MD, Takumi Yamada, MD, Vance Plumb, MD and G. Neal. Kay, MD. The University of Alabama in Birmingham, Birmingham, AL, Mobile Cardiology Associates, Mobile, ALIntroduction: The standard of care in many centers for pts requiring oral anticoagulation with warfarin who undergo cardiovascular implantable electronic device (CIED) implantation or replacement has been to continue warfarin throughout the perioperative period. This decreases the risk of bleeding as compared with bridging with heparin. However, it is unknown whether CIEDs can be safely implanted with uninterrupted dabigatran.Methods: We compared the outcome of patients undergoing CIED implantation, replacement, or system revision during uninterrupted OAC with either warfarin or dabigatran. The records of all patients undergoing CIED implantation, replacement or revision during uninterrupted OAC with dabigatran were reviewed and compared to a similar cohort of patients that underwent device implantation during uninterrupted anticoagulation with warfarin.Results: Dabigatran was continued on the day of CIED implant in 48 pts (age 66 + 12.4 yrs, 13F and 35M, 21 ICDs and 27 PMs). The procedure was a new implant in 25 pts, replacement


PO03-43

PULSE PRESSURE AND THE BENEFIT OF CARDIAC RESYNCHRONIZATION THERAPY AMONG PATIENTS WITH LEFT BUNDLE BRANCH BLOCK ENROLLED IN MADIT-CRTSaadia Sherazi, MD, Ilan Goldenberg, MD, Arthur Moss, MD, Scott Solomon, MD, David Huang, MD, Scott McNitt, MS, Abrar Shah, MD, Mehmet Aktas, MD, Wojciech Zareba, MD and Alon Barsheshet, MD. Heart Research Follow-up Program at University of Rochester, Rochester, NY, Brigham and Women’s Hospital, Cardiovascular Division, Boston, MA, Department of Electrophysiology University of Rochester, Rochester, NYIntroduction: Low pulse pressure (PP) is associated with poor clinical outcome among patients with systolic heart failure (HF). However, the relationship between PP and response to cardiac resynchronization therapy with defibrillator (CRT-D) is unknown.Methods: We evaluated the relationship between pre-implantation PP and echocardiographic response to CRT-D (defined as >15% reduction in left ventricular end systolic volume [LVESV] at 1 year) among 754 CRT-D patients with left bundle branch block (LBBB) enrolled in MADIT-CRT. The association between PP at 1 year and the risk for subsequent HF or death was evaluated using the Cox model adjusting for multiple variables.Results: Patients with high vs. low PP (>40 vs. <40 mmHG [lower quartile]) had a significantly greater reduction in LVESV, LV end diastolic volume, greater improvement in ejection fraction, and measures of LV dyssynchrony (p<0.01 for all comparisons). In multivariate analysis, the presence of high PP was associated with a 3.5-fold (p<0.001) increase in the likelihood of a positive echocardiographic response to CRT. At 1-year of follow-up, patients who had high PP (>40 mmHG, >lower quartile) experienced a significant reduction in the risk of subsequent HF or death compared to patients with low PP. (Adjusted hazard ratio = 0.58, p=0.005; and figure).Conclusion: Our findings suggest that high baseline PP is an independent predictor of echocardiographic response to CRT and high PP following device implantation is associated with improved subsequent clinical outcome.

PO03-44

ELECTROCARDIOGRAPHIC ABNORMALITIES ARE COMMON IN PATIENTS WITH IDIOPATHIC VENTRICULAR FIBRILLATION, BUT DO NOT OFFER PREDICTIVE VALUE IN REGARD TO FUTURE SERIOUS ARRHYTHMIC EVENTSRasmus Borgquist, MD, PhD and Pyotr G. Platonov, MD, PHD, FHRS. Arrhythmia Clinic, Lund, SwedenIntroduction: Patients presenting with cardiac arrest due to ventricular fibrillation without evidence of structural heart disease or channelopathies present a diagnostic and therapeutic challenge. Some data suggest that recurrence rate may be

PO03-42

VENTRICULAR INTRINSIC PREFERENCETM FEATURE REDUCES HEART FAILURE HOSPITALIZATIONS AND ASSOCIATED MEDICAL COSTS IN PACEMAKER PATIENTSBrett A. Faulknier, DO, Mark Richards, MD, PhD, Xiaoyi Min, PhD, Jeffery Snell, BA and Ranjan K. Thakur, MD. FACC WVU Physicians of Charleston Dept of Electrophysiology, Charleston, WV, Northwest Ohio Cardiology Consultants, Toledo, OH, St. Jude Medical, Sylmar, CA, Thoracic Cardiovascular Institute, Lansing, MIIntroduction: Previous analyses have demonstrated that pacemaker patients (pts) with higher %RV pacing (%RVP) burden incurred a higher risk for heart failure (HF) hospitalization (hosp) and cardiac death. This analysis assesses the clinical outcomes and HF hosp costs associated with the utilization of the ventricular intrinsic preference (VIPTM) feature to reduce %RVP.Methods: All non-CRT-P pacemaker pts from BRADYCARE completing their 12-month follow-up were divided into two groups: VIP ON and VIP OFF. Hosps were monitored and adjudicated, and a Cox proportional hazards model was used to compare the event-free survival from HF hosp between groups. Costs associated with hosps were based upon Medicare reimbursement data available to each facility for the associated Diagnosis Related Group (DRG) codes for inpatient hospital services and Ambulatory Payment Classification (APC) codes for outpatient services using MediRegs software.Results: A total of 2812 pts (VIP ON = 1530 pts; VIP OFF = 1282 pts) were analyzed. When adjusted for age, LVEF, NYHA functional class, and ischemic heart disease, VIP ON had a significantly lower risk of HF hosp than VIP OFF (hazard ratio = 0.48; 95% CI 0.24 - 0.98, p=0.04). VIP ON incurred fewer HF hosp expenditures per pt-years than VIP OFF ($29.74 vs. $159.67, P =0.007). See table; *denotes P = 0.004; ** denotes P = 0.007.Conclusion: Utilizing VIP to reduce %RV pacing leads to a reduced risk of HF hosp and reduced associated costs. Physicians should be encouraged to utilize this valuable feature in pacemaker patients.

VIP OFF VIP ON# pts analyzed 1,282 1,530Total FU time (yrs) 1,160 1,538# HF hospitalizations 28 8# days hospitalized for HF (days) 114 49Total HF hosp cost ($) $185,132 $45,723HF hosp cost per pt ($/pt) $144.41 $29.88*HF hosp cost per pt-yr ($/pt-yr) $159.67 $29.74**


and second generation antipsychotics were more commonly used by SCD cases. Second generation drugs were the most commonly used antipsychotics (6.3% of cases vs. 1.3% of controls, p<0.0001). Of the first generation antipsychotics, the butyrophenones were used more by cases (1.2 vs. 0.1%, P=0.007), while the phenothiazines showed a similar trend (1.1 vs. 0.4%, p=0.07). Third generation antipsychotics were rarely used (0.1% overall). No significant differences were observed in other psychiatric disorders (p≥0.14). A history of DM, CKD, COPD, and severe LV dysfunction were more common in cases; controls had a higher prevalence of HTN, documented CAD, and obesity. In a logistic regression model adjusted for age, gender and comorbidities, use of first or second generation antipsychotics was a significant predictor of SCD.Conclusion: In this population-based study, use of both first and second generation antipsychotic drugs was independently associated with the risk of SCD, after adjusting for age, gender, documented schizophrenia and other existing co-morbidities.

PO03-46

MECHANISMS OF PULSELESS ELECTRICAL ACTIVITY VERSUS VENTRICULAR FIBRILLATION: DO AUTOPSIES PROVIDE INSIGHT?Carmen Teodorescu, MD, PhD, Audrey Uy-Evanado, MD, Kyndaron Reinier, PhD, Jo Ayala, BS, Ronald Mariani, BS, Karen Gunson, MD, Jonathan Jui, MD, MPH and Sumeet S. Chugh, MD. Cedars-Sinai Heart Institute, Los Angeles, CA, Oregon Health and Science University, Portland, ORIntroduction: Cardiac arrest manifesting with pulseless electrical activity (PEA) is rising in prevalence and has a significantly worse outcome than presentation with ventricular fibrillation/ tachycardia (VF/VT). Especially since the reasons for this paradigm shift remain unknown, focused and detailed autopsy study has the potential to contribute additional mechanistic insight.Methods: From an ongoing population-based study of sudden cardiac death (SCD) in a metro region of the Northwestern US (approx. one million residents), cases of sudden death were ascertained prospectively using multiple sources (first responders and the Medical Examiner). The initial rhythm was identified at the time of presentation with sudden cardiac arrest.Detailed autopsy reports of out-of hospital PEA (n= 43) and VF/VT (n= 108) cases were evaluated and compared.Results: There was no difference in the mean age of PEA vs. VF/VT (46.6±10.7 vs. 44.6±11.7 years, p= 0.32). VF/VT cases were more likely to be male (86.1% vs. 69.7%, p= 0.02). Out of the total, 62.8% of PEA cardiac arrests and 92.6% of VF/VT were identified as being of primary cardiac origin. Atherosclerotic heart disease was the main cause of death in both groups, with a significantly higher proportion in VF/VT compared to PEA (63.9% vs. 32.6%, p= 0.0005). Hypertrophic cardiomyopathy was found in 4.6% of PEA and 13.0% of VF/VT (p= 0.24). ARVD was reported in 1 PEA case and 1 VF/VT case had congenital heart disease. Idiopathic arrhythmia was listed in 16.3% of PEA and 11.1% of VF/VT (p= 0.39). Pulmonary embolism was only found in 2 PEA cases and 1 VF/VT. Drug overdose was reported in 16.3% of PEA vs. 4.6% of VF/VT (p= 0.04). Other natural and unnatural causes of death such as aortic dissection, acute pancreatitis, terminal illness, traumatic pneumothorax and asphyxia were reported in small proportions (one-three cases for each cause of sudden death).Conclusion: On detailed post-mortem evaluation, subjects manifesting with PEA were more likely to present in the setting of drug overdose and less likely to have findings of atherosclerotic heart disease. Contrary to clinical expectations, pulmonary embolism was a rare finding in either group.

as high as 10% per year, however long term prognosis and development of conclusive cardiac diagnosis remains unclear in this group of patients.Methods: We followed 28 consecutive patients with idiopathic VF (age at event 38±16 years, 71% male) for a mean time of 7±6 years (range 1-22 years). Ischemic heart disease was ruled out in all patients. All patients had structurally normal hearts and at the time of VF did not fulfil criteria for any of the known channelopathies. All patients were implanted with an ICD, and follow-up included device-based data as well as clinical outcome and EC.Results: At initial evaluation, 54% had abnormal ECG findings, compared to 63% at FU (see table), however none received any definite diagnosis by the end of follow-up. All patients survived. Five patients had appropriate ICD therapy due to VT (n=2) or VF (n=3) at a median of 16 months after implant. Three patients had inappropriate ICD chocks. Neither clinical, imaging nor ECG findings could predict appropriate or inappropriate ICD interventions.Conclusion: Contrary to earlier reports, the vast majority of patients who survived idiopathic VF in our cohort had no VF recurrence during long-term follow-up. The cause of the index event therefore remains obscure. Subtle ECG abnormalities are common but not specific and do not offer a predictive value for future appropriate ICD therapy.

PO03-45

FIRST VS. SECOND GENERATION ANTI-PSYCHOTIC AGENTS AND INCREASED RISK OF SUDDEN CARDIAC DEATHAudrey Uy-Evanado, MD, Carmen Teodorescu, MD, PhD, Kyndaron Reinier, PhD, Karen Gunson, MD, Jonathan Jui, MD, MPH and Sumeet S. Chugh, MD. Cedars-Sinai Medical Center, Los Angeles, CA, Oregon Health and Science University, Portland, ORIntroduction: We previously reported an independent association between anti-psychotic drugs and increased risk of sudden cardiac death (SCD) independent of treatment indication. Due to implications of these findings for ongoing patient care, we further evaluated the effects of specific classes of anti-psychotic agents on risk of SCD.Methods: From a large ongoing community-based study in the Northwestern US, we identified SCD cases and controls age ≥ 18 years with medical records and medications available for review, and analyzed the SCD risk of taking antipsychotics. We compared demographics, clinical characteristics, and use of first and second generation antipsychotics using Pearson’s chi-square tests and independent samples t-tests.Results: Among 1544 cases (64.4% male, 67.0±15.7 yrs) and 774 controls (66.2% males, 67.3±11.5 yrs), mean age and gender distribution were similar (p≥0.08). Compared to controls, cases had a higher prevalence of schizophrenia (2.5 vs. 0.5%, p=0.0009) and use of antipsychotic (8.2 vs. 1.9%, p<0.0001) and anti-depressant (29.5 vs 25.3%, p=0.03) agents. First

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