AB

ST

RA

CT

S

72 Heart, Lung and CirculationAbstracts of the ASCTS Annual Scientific Meeting 2007 2009;18:65–88

temic blood pressure. Echocardiography was performedwith a hand held transducer directly on the LV apex. Mod-ification of systolic anterior motion of the anterior leaflet(SAM) and LVOTO was performed by manipulation of car-diac output and valve cinching. The valve prostheses usedwere Medtronic Mosaic and St Jude Biocor porcine stentedvalves. Non-commercial circular annuloplasty rings werealso used.

Results: Twenty-five adult merino cross sheep under-went insertion of 50 mitral prostheses. In 4 sheep 33 mmSt Jude and Medtronic valves were used as the twoprostheses. SAM was identified with one of the St Judevalves suggesting that high profile valves do not have anincreased predisposition to SAM. For the 18 size 33 mmvalves used, 5 sheep developed echocardiographic evi-dence of SAM with monometer gradients from 40 to100 mmHg. There was no difference between the St Judeand Medtronic valves. Eight sheep underwent insertionof a 27 mm bioprosthesis and 6 of 8 sheep developedSAM with manometer gradients of 40–100 mmHg. Sevenbioprostheses were subjected to anteroposterior cinchingfollowing development of SAM. This resulted in reductionor abolition of the SAM in 6 of 7 sheep. Six bioprosthe-ses were subjected to lateral cinching in the absence ofSAM. In 2 sheep, SAM was induced by lateral cinching. In6 sheep a bioprosthesis was positioned with 1 stent directlyunder the mid point of the anterior leaflet. This was asso-

recurrent MR and re-operation. Also, resectional tech-niques are not suited to extensive posterior leaflet prolapseor where there is potentially a deficiency of tissue postresection.

We present our experience with a leaflet preservingtechnique of restoring valve competence without resec-tion. Prolapse was corrected with 4/0 Gortex artificialchordae to the posterior leaflet (62 patients) (either bythe “Loop” technique or individually inserted into thecorresponding papillary muscle), or papillary muscle re-implantation (1 patient).

From February 2005 to July 2007, 63 patients with iso-lated posterior leaflet prolapse have undergone a valvesparing repair technique. There were 45 males, 18 females,age range from 25 to 88 years with a mean of 55 years.NYHA class I (10), II (28), IV (5). Preoperative ejection frac-tion ranged from 40% to 77% with an average of 57%. Allpatients had severe 3-4/4 MR.

Associated procedures included CABG: 8, PFO Clo-sure: 1, Tricuspid valve annuloplasty: 5, CABG + TVA: 1,TVA + RFA: 1, AVR + PFO Closure: 1.

Mortality: There were no intraoperative deaths, and no30 day mortality. Second pump runs were required in 2patients and a third pump run in 1 (all with associatedSAM). On table post pump TOW showed 0-trace MR in 38patients with 0–1 in 2 patients. SAM occurred in 4 patients,3 required repeat pump runs for correction.

ciated with an outflow tract gradient in all sheep and withechocardiographic evidence of SAM in 4 of the 6. Volumeloading from the CPB machine precipitated rather thanabolished SAM. A composite 33/25 mm valve was insertedin 3 sheep with echocardiographic evidence of SAM in 1.

Conclusion: A reduction of the anteroposterior diam-eter of a bioprosthesis reduces the likelihood of SAM.However, reducing the anteroposterior diameter byundersising the bioprosthesis does not reduce the like-lihood of SAM. Positioning stent posts beneath the midpoint of the anterior leaflet increases the likelihood ofoutflow obstruction. A non-circular stented bioprosthesiswith a large anterior leaflet may permit safe retention ofthe anterior leaflet.

doi:10.1016/j.hlc.2008.11.023

14

Leaflet preservation in posterior leaflet repair for degen-erative mitral regurgitation

Michael Gardner, Trevor Fayers

St. Andrews, Prince Charles and Holy Spirit Hospitals, Aus-tralia

Posterior leaflet prolapse is the most common cause ofmitral regurgitation in patients with degenerative mitralvalve disease. Repair has traditionally been performedby resecting the prolapsing segment of posterior leaflet(quadrangular or triangular resection) with generallygood early and long term results. However there is an inci-dence of systolic anterior movement (SAM) post repair,

Postoperative complications: Re-exploration for bleedingin 1 patient, postoperative pericardial collection requiringdrainage: 2. New atrial fibrillation occurred in 15 patients.There were no thrombo-embolic events and no neuro-logic sequelae in this cohort. No patients required PPMplacement.

Long term follow up is incomplete. Patients with SAMrequiring correction appeared to have the poorest out-comes with 1–2 MR at one year.

Early results indicate that the valve sparing techniquesis reliable and effective in correcting posterior leaflet pro-lapse and eliminating mitral regurgitation. Long termfollow up will be required to assess the efficacy of thistechnique.

doi:10.1016/j.hlc.2008.11.024

15

Estimating the intertrigonal distance of the mitral valvenon-invasively: An observational study

Shamil D. Cooray 1,, Elli Tutungi 2, Joseph Mezzatesta 2,

Randall Moshinsky 3, Aubrey A. Almeida 3

1 Department of Surgery, Monash Medical Centre, Clayton,Australia2 Department of Anaesthesia, Monash Medical Centre, Clayton,Australia3 The Epworth Centre, Richmond, Australia

Introduction: The implantation of an accurately sizedannuloplasty band (ab) is essential to an effective mitral