Circulation-1998--1949-84

Guidelines for the Management of Patients WithValvular Heart Disease

Executive SummaryA Report of the American College of Cardiology/American Heart

Association Task Force on Practice Guidelines (Committee onManagement of Patients With Valvular Heart Disease)

Committee Members: Robert O. Bonow, MD, FACC, Chair; Blase Carabello, MD, FACC;Antonio C. de Leon, Jr, MD, FACC; L. Henry Edmunds, Jr, MD, FACC;

Bradley J. Fedderly, MD, FAAFP; Michael D. Freed, MD, FACC; William H. Gaasch, MD, FACC;Charles R. McKay, MD, FACC; Rick A. Nishimura, MD, FACC; Patrick T. O’Gara, MD, FACC;

Robert A. O’Rourke, MD, FACC; Shahbudin H. Rahimtoola, MD, FACC

Task Force Members: James L. Ritchie, MD, FACC, Chair; Melvin D. Cheitlin, MD, FACC;Kim A. Eagle, MD, FACC; Timothy J. Gardner, MD, FACC; Arthur Garson, Jr, MD, MPH, FACC;

Raymond J. Gibbons, MD, FACC; Richard O. Russell, MD, FACC;Thomas J. Ryan, MD, FACC; Sidney C. Smith, Jr, MD, FACC

I. IntroductionThis executive summary and recommendations appears in theNovember 3, 1998, issue ofCirculation. The guidelines in theirentirety, including the ACC/AHA Class I, II, and III recommen-dations, are published in the November 1, 1998, issue of theJournal of the American College of Cardiology. Reprints of boththe full text and the executive summary and recommendationsare available from both organizations.

During the past 2 decades, major advances have occurredin diagnostic techniques, the understanding of natural history,and interventional cardiological and surgical procedures for

patients with valvular heart disease. The information basefrom which to make clinical management decisions hasgreatly expanded in recent years, yet in many situations,management issues remain controversial or uncertain. Unlikemany other forms of cardiovascular disease, there is a scarcityof large-scale multicenter trials addressing the diagnosis andtreatment of valvular disease from which to derive definitiveconclusions, and the literature represents primarily the expe-riences reported by single institutions in relatively smallnumbers of patients.

The Committee on Management of Patients With ValvularDisease was given the task of reviewing and compiling thisinformation base and making recommendations for diagnostictesting, treatment, and physical activity. These guidelines followthe format established in previous American College of Cardi-ology/American Heart Association (ACC/AHA) guidelines forclassifying indications for diagnostic and therapeutic procedures:

Class I: Conditions for which there is evidence and/orgeneral agreement that a given procedure or treatment isuseful and effective

Class II: Conditions for which there is conflicting evi-dence and/or a divergence of opinion about the usefulness/efficacy of a procedure or treatment

IIa. Weight of evidence/opinion is in favor ofusefulness/efficacy

IIb. Usefulness/efficacy is less well established byevidence/opinion.

Class III: Conditions for which there is evidence and/orgeneral agreement that the procedure/treatment is not usefuland in some cases may be harmful.

This task force report overlaps with several previously pub-lished ACC/AHA guidelines for cardiac imaging and diagnostictesting, including the Guidelines for Clinical Use of CardiacRadionuclide Imaging,1 the Guidelines for the Clinical Applica-tion of Echocardiography,2 the Guidelines for Exercise Testing,3

When citing this document, the American College of Cardiology andthe American Heart Association recommend that the following format beused: Bonow RO, Carabello B, de Leon AC Jr, Edmunds LH Jr, FedderlyBJ, Freed MD, Gaasch WH, McKay CR, Nishimura RA, O’Gara PT,O’Rourke RA, Rahimtoola SH. ACC/AHA guidelines for the manage-ment of patients with valvular heart disease: executive summary. Areport of the American College of Cardiology/American Heart Associa-tion Task Force on Practice Guidelines (Committee on Management ofPatients With Valvular Heart Disease).Circulation.1998;98:1949-1984.

“Guidelines for the Management of Patients With Valvular HeartDisease: Executive Summary” was approved by the American College ofCardiology in August 1998 and the American Heart Association ScienceAdvisory and Coordinating Committee in July 1998.

A single reprint of this document (Executive Summary) is available bycalling 800-242-8721 (US only) or writing the American Heart Associ-ation, Public Information, 7272 Greenville Avenue, Dallas, TX 75231-4596. Ask for reprint No. 71-0154. To obtain a reprint of the full text ofthe Guidelines published in the November 1998 issue of theJournal ofthe American College of Cardiology, ask for reprint No. 71-0153. Topurchase additional reprints, specify version and reprint number: up to999 copies, call 800-611-6083 (US only) or fax 413-665-2671; 1000 ormore copies, call 214-706-1466, fax 214-691-6342, or [email protected]. To make photocopies for personal or educationaluse, call the Copyright Clearance Center, 978-750-8400.

Circulation. 1998;98:1949-1984.© 1998 American College of Cardiology and American Heart Asso-

ciation, Inc.

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ACC/AHA Practice Guidelines

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and the Guidelines for Coronary Angiography.4 Although theseguidelines are not intended to include detailed informationcovered in previous guidelines on the use of imaging anddiagnostic testing, a discussion of the indications for these testsin the evaluation and treatment of patients with valvular heartdisease is an essential component of this summary.

The committee emphasizes the fact that many factorsultimately determine the most appropriate treatment of indi-vidual patients with valvular heart disease in individualcommunities. These factors include the availability of diag-nostic equipment and expert diagnosticians, the expertise ofinterventional cardiologists and surgeons, and notably thewishes of well-informed patients. Therefore, deviation fromthese guidelines may be appropriate in some circumstances.These guidelines are written with the assumption that adiagnostic test can be performed and interpreted with skilllevels consistent with previously reported ACC training andcompetency statements and ACC/AHA guidelines, that inter-ventional cardiological and surgical procedures can be per-formed by highly trained practitioners within acceptablesafety standards, and that the resources necessary to performthese diagnostic procedures and provide this care are readilyavailable. This is not true in all geographic areas, whichfurther underscores the committee’s position that these rec-ommendations are guidelines and not rigid requirements.

II. General PrinciplesA. Evaluation of the Patient With aCardiac MurmurA heart murmur may have no pathological significance or maybe an important clue to the presence of valvular, congenital, orother structural abnormalities of the heart. Most systolic heartmurmurs do not signify cardiac disease, and many are related tophysiological increases in blood flow velocity. In other in-stances, a heart murmur may be an important clue to thediagnosis of undetected cardiac disease that may be importanteven when asymptomatic or that may define the reason forcardiac symptoms. In these situations, various noninvasive orinvasive cardiac tests may be necessary to establish a firmdiagnosis and form the basis for rational treatment of anunderlying disorder. Two-dimensional (2-D) and Doppler echo-cardiography is particularly useful in this regard. Diastolicmurmurs virtually always represent pathological conditions andrequire further cardiac evaluation, as do most continuous mur-murs. Continuous “innocent” murmurs include venous hums andmammary souffle´s.

An important consideration in a patient with a cardiac murmuris the presence or absence of symptoms. Many asymptomaticchildren and young adults with grade 2/6 midsystolic murmursand no other cardiac physical findings need no further cardiacworkup after the initial history and physical examination. Aparticularly important group is the large number ofasymptom-atic elderly patients, many with systemic hypertension, whohave midsystolic murmurs related to sclerotic aortic valveleaflets, flow into tortuous, noncompliant great vessels, or acombination of these. Such murmurs must be distinguished frommurmurs caused by mild to severe valvular aortic stenosis (AS),which is prevalent in this age group.

Although echocardiography usually provides more specificand often quantitative information about the significance of aheart murmur and may be the only test needed, the electrocar-diogram (ECG) and chest x-ray are readily available and mayhave already been obtained. The absence of ventricular hyper-trophy, atrial abnormality, arrhythmias, conduction abnormali-ties, prior myocardial infarction, and evidence of active ischemiaon the ECG provides useful negative information at a relativelylow cost. Abnormal findings on the ECG such as ventricularhypertrophy or a prior infarction should lead to a more extensiveevaluation, including 2-D and Doppler echocardiography.

EchocardiographyEchocardiography is an important noninvasive method forassessing the significance of cardiac murmurs. 2-D echocar-diography may indicate abnormal valvular motion and mor-phology but usually does not indicate the severity of valvularstenosis or regurgitation except in mitral stenosis (MS).Doppler echocardiography identifies increased velocity offlow across stenotic valves from which the severity ofstenosis may be determined. The presence of an abnormalregurgitant jet on Doppler color flow imaging indicatesvalvular regurgitation and provides semiquantitative informa-tion about its severity.

Although 2-D echocardiography and color flow Dopplerimaging can provide important information on patients withcardiac murmurs, these tests are not necessary for all patientswith cardiac murmurs and usually add little but expense in theevaluation of asymptomatic patients with short grade 1 to 2midsystolic murmurs and otherwise normal physical findings.Alternatively, if the diagnosis is still questionable aftertransthoracic echocardiography, transesophageal echocardi-ography or cardiac catheterization may be appropriate. Manyrecent studies indicate that Doppler ultrasound devices arevery sensitive and may detect valvular regurgitation throughthe tricuspid and pulmonic valves in a large percentage ofhealthy subjects and through left-sided valves (particularlythe mitral) in a variable but lower percentage.

General recommendations for performing 2-D and Dopplerechocardiography in asymptomatic and symptomatic patientswith heart murmurs follow. Of course, individual exceptionsto these indications may exist.

Recommendations for Echocardiography in AsymptomaticPatients With Cardiac Murmurs

Indication Class

1. Diastolic or continuous murmurs. I

2. Holosystolic or late systolic murmurs. I

3. Grade 3 or greater midsystolic murmurs. I

4. Murmurs associated with abnormal physical findingson cardiac palpation or auscultation.

IIa

5. Murmurs associated with an abnormal ECG or chestx-ray.

IIa

6. Grade 2 or softer midsystolic murmur identified asinnocent or functional by an experienced observer.

III

7. To detect “silent” aortic regurgitation or mitralregurgitation in patients without cardiac murmurs, thenrecommend endocarditis prophylaxis.

III

1950 ACC/AHA Guidelines Executive Summary



Recommendations for Echocardiography in SymptomaticPatients With Cardiac Murmurs

Indication Class

1. Symptoms or signs of congestive heart failure,myocardial ischemia, or syncope.

I

2. Symptoms or signs consistent with infectiveendocarditis or thromboembolism.

I

3. Symptoms or signs likely due to noncardiac diseasewith cardiac disease not excluded by standardcardiovascular evaluation.

IIa

4. Symptoms or signs of noncardiac disease with anisolated midsystolic “innocent” murmur.

III

There are very few data addressing the cost-effectivenessof various approaches to the patient undergoing medicalevaluation of a cardiac murmur. Optimal auscultation bywell-trained examiners who can recognize an insignificantmidsystolic murmur with confidence results in less frequentuse of expensive additional testing to define murmurs that donot indicate cardiac pathology.

Many murmurs in asymptomatic adults are innocent andhave no functional significance. Such murmurs have thefollowing characteristics: (1) grade 1 to 2 intensity at the leftsternal border, (2) a systolic ejection pattern, (3) normalintensity and splitting of the second heart sound, (4) no otherabnormal sounds or murmurs, and (5) no evidence of ven-tricular hypertrophy or dilatation and the absence of increasedmurmur intensity with the Valsalva maneuver. Such murmursare especially common in high-output states such aspregnancy.

In the evaluation of heart murmurs, the purposes ofechocardiography are to (1) define the primary lesion in termsof etiology and severity, (2) define hemodynamics, (3) definecoexisting abnormalities, (4) detect secondary lesions, (5)evaluate cardiac chamber size and function, (6) establish areference point for future comparisons, and (7) reevaluate thepatient after an intervention.

B. Endocarditis and Rheumatic Fever Prophylaxis

1. Endocarditis ProphylaxisEndocarditis is a serious illness associated with significantmortality. Its prevention by appropriate administration ofantibiotics before procedures expected to produce bacteremiamerits serious consideration. Several issues must be consid-ered in generating recommendations for endocarditis prophy-laxis. It has been suggested that the risk of endocarditis inpatients with preexisting cardiac disorders be classified asrelatively high risk, moderate risk, and low or negligible risk,as determined by the cardiac disorder. Guidelines for theprevention of endocarditis have been issued by the AmericanHeart Association,5 and the current committee endorses thoseguidelines, with the following comments:

• This committee recommends prophylaxis in hypertrophic cardiomy-opathy only when there is latent or resting obstruction.

• Patients with mitral valve prolapse (MVP) without regurgitationrequire additional clinical judgment. Indications for antibiotic prophylaxisin MVP are discussed in section III.D. Patients who do not have mitralregurgitation (MR) but do have echocardiographic evidence of thickening

and/or redundancy of the valve leaflets and especially men >45 yearsmay be at increased risk for bacterial endocarditis.5 Additionally, approx-imately one third of patients with MVP without MR at rest may haveexercise-induced MR. Some patients may exhibit MR at rest on 1 occasionand none on others. There are no data available to address this latterissue, and at present, the decision must be left to clinical judgment,taking into account the nature of the invasive procedure, the previoushistory of endocarditis, and the presence or absence of valve thickeningand/or redundancy.

• In patients with echocardiographic evidence of physiological MR inthe absence of a murmur and with structurally normal valves, prophylaxisis not recommended. The committee also does not recommend prophy-laxis for physiological tricuspid and pulmonary regurgitation detected byDoppler in the absence of a murmur, as such findings occur in a largenumber of normal individuals and the risk of endocarditis is extremelylow. Recommendations regarding Doppler echocardiography for purposesof antibiotic prophylaxis in patients who have received anorectic drugsare given in section III.H. of these guidelines.

Various dental and/or surgical procedures are associatedwith varying degrees and frequencies of bacteremia. Recom-mendations for endocarditis prophylaxis, as determined bythe dental and/or surgical procedure, are provided in full inthe AHA recommendations for prevention of bacterial endo-carditis5 and the full text of these guidelines.

2. Rheumatic Fever ProphylaxisRheumatic fever is an important cause of valvular heartdisease worldwide. In the United States (and Western Eu-rope), cases of acute rheumatic fever have been uncommonsince the 1970s. However, starting in 1987, an increase incases has been observed.

Patients who have had an episode of rheumatic fever areat high risk of developing recurrent episodes of acuterheumatic fever. Patients who develop carditis are espe-cially prone to similar episodes with subsequent attacks.Thus, secondary prevention of subsequent rheumatic feverrecurrences is of great importance. Continuous antimicro-bial prophylaxis has been shown to be effective. Anyonewho has had rheumatic fever with or without carditis(including MS) should have prophylaxis for recurrentrheumatic fever. Lifelong prophylaxis is recommended forpatients who have had carditis and residual valve diseaseand are likely to come in contact with populations with ahigh prevalence of streptococcal infections, such as teach-ers and day-care workers. Guidelines for primary andsecondary prevention have been published by the AHA6

and are reproduced in the full text of these guidelines.

III. Specific Valve LesionsA. Aortic Stenosis

Grading the Degree of StenosisThe aortic valve area must be reduced to one fourth its normalsize before significant changes in the circulation occur. Becausethe normal adult valve orifice is'3.0 to 4.0 cm2, an area$0.75to 1.0 cm2 is usually not considered severe AS. In large patients,a valve area of 1.0 cm2 may be severely stenotic, whereas a valvearea of 0.7 cm2 may be adequate for a smaller patient.

The committee used a variety of hemodynamic and naturalhistory data to grade the degree of AS as mild (area.1.5cm2), moderate (area.1.0 to 1.5 cm2), or severe (area#1.0

ACC/AHA Task Force November 3, 1998 1951



cm2). When stenosis is severe and cardiac output is normal,the mean transvalvular pressure gradient is generally.50 mm Hg. Some patients with severe AS remain asymp-tomatic, whereas others with only moderate stenosis developsymptoms. Therapeutic decisions, particularly those relatedto corrective surgery, are based largely on the presence orabsence of symptoms. Thus, the absolute valve area (ortransvalvular pressure gradient) is not usually the primarydeterminant of the need for aortic valve replacement (AVR).

An ejection systolic murmur may be heard in the presenceof a normal valve, one that is thickened and minimallycalcified, and one that is stenotic. The 3 conditions must bedistinguished.

Natural HistoryThe natural history of AS in the adult consists of aprolonged latent period in which morbidity and mortalityare very low. The rate of progression of the stenotic lesionhas been estimated in a variety of hemodynamic studiesperformed largely in patients with moderate AS. Cardiaccatheterization and Doppler echocardiographic studies in-dicate that some patients exhibit a decrease in valve area of0.1 to 0.3 cm2 per year; the average rate of change is'0.12cm2 per year. The systolic pressure gradient across thevalve may increase by as much as 10 to 15 mm Hg peryear. However, more than half of the reported patientsshowed little or no progression over a 3- to 9-year period.Although it appears that progression of AS can be morerapid in patients with degenerative calcific disease than inthose with congenital or rheumatic disease, it is notpossible to predict the rate of progression in an individualpatient.

Eventually, symptoms of angina, syncope, or heart failuredevelop after a long latent period, and the outlook changesdramatically. After onset of symptoms, average survival is,2 to 3 years. Thus, the development of symptoms identifiesa critical point in the natural history of AS.

Many asymptomatic patients with severe AS developsymptoms within a few years and require surgery. Theincidence of angina, dyspnea, or syncope in asymptomaticpatients with Doppler outflow velocities$4 m/s has beenreported to be as high as 38% after 2 years and 79% after 3years. Therefore, patients with severe AS require carefulmonitoring for development of symptoms and progressivedisease.

Sudden death is known to occur in patients with severe ASbut has rarely been documented to occur without priorsymptoms. Recent prospective echocardiographic studiesprovide important data on the rarity of sudden death inasymptomatic patients. Although sudden death does occa-sionally occur in the absence of preceding symptoms inpatients with AS, it must be an uncommon event—probably,1% per year.

Management of the Asymptomatic PatientPatients with the physical findings of AS should undergoselected laboratory examinations, including an ECG, a chestx-ray, and an echocardiogram. The 2-D echocardiogram isvaluable for confirming the presence of aortic valve diseaseand determining left ventricular (LV) size and function,

degree of hypertrophy, and presence of other associated valvedisease. In most patients, the severity of the stenotic lesioncan be defined with Doppler echocardiographic measure-ments of a mean transvalvular pressure gradient and a derivedvalve area as discussed in the ACC/AHA Guidelines for theClinical Application of Echocardiography.2

Recommendations for Echocardiography in Aortic Stenosis

Indication Class

1. Diagnosis and assessment of severity of AS. I

2. Assessment of LV size, function, and/or hemodynamics. I

3. Reevaluation of patients with known AS with changingsymptoms or signs.

I

4. Assessment of changes in hemodynamic severity andventricular compensation in patients with known ASduring pregnancy.

I

5. Reevaluation of asymptomatic patients with severe AS. I

6. Reevaluation of asymptomatic patients with mild tomoderate AS and evidence of LV dysfunction orhypertrophy.

IIa

7. Routine reevaluation of asymptomatic adult patients withmild AS having stable physical signs and normal LV sizeand function.

III

From the ACC/AHA Guidelines for the Clinical Application ofEchocardiography.2

In some patients, it may be necessary to proceed with cardiaccatheterization and coronary angiography at the time of initialevaluation. This is appropriate, for example, if there is adiscrepancy between the clinical and echocardiographic ex-aminations or if the patient is symptomatic and AVR isplanned.

Exercise testing in adults with AS has been discouragedlargely because of concerns about safety. Furthermore,when used to assess the presence or absence of coronaryartery disease (CAD), the test has limited diagnosticaccuracy. Certainly, exercise testing should not be per-formed in symptomatic patients. However, in asymptom-atic patients, exercise testing is safe and may provideinformation not uncovered during the initial clinical eval-uation. Exercise testing in asymptomatic patients should beperformed only under the supervision of an experiencedphysician, with close monitoring of blood pressure and theECG. Such testing can identify patients who have a limitedexercise capacity or even exercise-induced symptoms de-spite a negative medical history. An abnormal hemody-namic response (eg, hypotension) in a patient with severeAS is sufficient reason to consider AVR.

The frequency of follow-up visits to the physician dependson the severity of valvular stenosis and in part on the presenceof comorbid conditions. Recognizing that an optimal sched-ule for repeated medical examinations has not been defined,many physicians perform an annual history and physicalexamination on patients with mild AS. Those with moderateand severe AS should be examined more frequently. Patientsshould be advised to promptly report the development of anyexertional chest discomfort, dyspnea, lightheadedness, orsyncope.




Echocardiographic studies can be an important part of anintegrated approach to the asymptomatic patient. Currentunderstanding of the natural history of AS and indications forsurgical intervention do not support the use of annual echo-cardiographic studies to assess changes in valve area. How-ever, serial echocardiograms are helpful for assessingchanges in LV hypertrophy and function. Therefore, inpatients with severe AS, a yearly echocardiogram may beappropriate. In patients with moderate AS, serial studiesevery 2 years or so are satisfactory, and in patients with mildAS, serial studies can be performed every 5 years. Echocar-diography should be performed more frequently if there is achange in clinical findings.

Recommendations for activity are based on the clinicalexamination, with special emphasis on the hemodynamicseverity of the stenotic lesion. Recommendations regardingparticipation in competitive athletics have been published bythe Task Force on Acquired Valvular Heart Disease of the26th Bethesda Conference.7 Patients with severe AS shouldbe advised to limit activity to relatively low levels.

Indications for Cardiac CatheterizationIn patients with AS, the indications for cardiac catheterizationand angiography are to assess the coronary circulation andconfirm or clarify the clinical diagnosis. In preparation forAVR, coronary angiography is indicated in patients suspectedof having CAD, as discussed in section VIII. If the clinicaland echocardiographic data are typical of severe isolated AS,coronary angiography may be all that is needed before AVR.Complete left- and right-heart catheterization may be neces-sary to assess the hemodynamic severity of AS if there is adiscrepancy between clinical and echocardiographic data orevidence of associated valvular or congenital disease orpulmonary hypertension.

Recommendations for Cardiac Catheterization inAortic Stenosis

Indication Class

1. Coronary angiography before AVR in patients at risk forCAD (see section VIII.B. of these guidelines).

I

2. Assessment of severity of AS in symptomatic patientswhen AVR is planned or when noninvasive tests areinconclusive or there is a discrepancy with clinicalfindings regarding severity of AS or need for surgery.

I

3. Assessment of severity of AS before AVR whennoninvasive tests are adequate and concordant withclinical findings and coronary angiography is notneeded.

IIb

4. Assessment of LV function and severity of AS inasymptomatic patients when noninvasive tests areadequate.

III

The pressure gradient across a stenotic valve is related tothe valve orifice area and transvalvular flow. Thus, in thepresence of depressed cardiac output, relatively low pressuregradients are frequently obtained in patients with severe AS.On the other hand, during exercise or other high-flow states,systolic gradients can be measured in minimally stenoticvalves. For these reasons, complete assessment of AS re-quires (1) measurement of transvalvular flow, (2) determina-

tion of the transvalvular pressure gradient, and (3) calculationof the effective valve area. Careful attention to detail withaccurate measurements of pressure and flow is important,especially in patients with low cardiac output or a lowtransvalvular pressure gradient.

Patients with severe AS and low cardiac output often presentwith only modest transvalvular pressure gradients (ie,,30 mm Hg). Such patients can be difficult to distinguish fromthose with low cardiac output and only mild to moderate AS. Inboth situations, the low-flow state and low pressure gradientcontribute to a calculated effective valve area that can meetcriteria for severe AS. The standard valve area formula is lessaccurate and is known to underestimate the valve area inlow-flow states; under such conditions, it should be interpretedwith caution. Although valve resistance is less sensitive to flowthan valve area, resistance calculations have not been proved tobe substantially better than valve area calculations.

In patients with low gradient stenosis and what appears tobe moderate to severe AS, it may be useful to determine thetransvalvular pressure gradient and calculate valve area andresistance during a baseline state and again during exercise orpharmacological (ie, dobutamine infusion) stress. Patientswho do not have true, anatomically severe stenosis exhibit anincrease in the valve area during an increase in cardiac output.In patients with severe AS, these changes may result in acalculated valve area that is higher than the baseline calcu-lation but that remains in the severe range, whereas in patientswithout severe AS, the calculated valve area will fall outsidethe severe range with administration of dobutamine andindicate that severe AS is not present.

Indications for Aortic Valve ReplacementIn the vast majority of adults, AVR is the only effectivetreatment for severe AS. However, younger patients may becandidates for valvotomy (see section VI.A.).

1. Symptomatic Patients.Patients with angina, dyspnea, orsyncope exhibit symptomatic improvement and an increase insurvival after AVR. Outcome is similar in patients withnormal LV function and those with moderate depression ofcontractile function. The depressed ejection fraction in manypatients in this latter group is caused by excessive afterload(afterload mismatch), and LV function improves after AVRin such patients. If LV dysfunction is not caused by afterloadmismatch, then improvement in LV function and resolutionof symptoms may not be complete after valve replacement.Survival is still improved in this setting with the possibleexception of patients with severe LV dysfunction caused byCAD. Therefore, in the absence of serious comorbid condi-tions, AVR is indicated in virtually all symptomatic patientswith severe AS. However, patients with severe LV dysfunc-tion, particularly those with so-called low gradient AS,represent a difficult management decision (see above). AVRshould not be performed in such patients when they do nothave anatomically severe stenosis. In patients with severe AS,even those with a low transvalvular pressure gradient, AVRresults in hemodynamic improvement and better functionalstatus.




2. Asymptomatic Patients.Management decisions in asymp-tomatic patients are more controversial. The combined risk ofsurgery and late complications of a prosthesis generallyexceed the possibility of preventing sudden death and pro-longing survival in all asymptomatic patients, as discussedpreviously. Despite these considerations, some difference ofopinion persists regarding indications for AVR in asymptom-atic patients. It is reasonable to attempt to identify patientswho may be at especially high risk of sudden death withoutsurgery, although data supporting this approach are limited.Patients in this subgroup include those with an abnormalresponse to exercise (eg, hypotension), LV systolic dysfunc-tion or marked/excessive LV hypertrophy, or evidence ofsevere AS. However, it should be recognized that such“high-risk” patients are rarely asymptomatic.

3. Patients Undergoing Coronary Artery Bypass Surgery.Patients with severe AS, with or without symptoms, whoare undergoing coronary artery bypass surgery shouldundergo AVR at the time of revascularization. Similarly,patients with severe AS undergoing surgery on othervalves (such as mitral valve repair) or the aortic rootshould also undergo AVR as part of the surgical procedure.Patients with moderate AS (for example, gradient$30 mm Hg) may warrant AVR at the time of coronaryartery bypass surgery or surgery on the mitral valve oraortic root. However, controversy persists regarding indi-cations for concomitant AVR at the time of coronary arterybypass surgery in patients with milder forms of AS asdiscussed in section VIII.D.

Recommendations for Aortic Valve Replacement inAortic Stenosis

Indication Class

1. Symptomatic patients with severe AS. I

2. Patients with severe AS undergoing coronary arterybypass surgery.

I

3. Patients with severe AS undergoing surgery on the aortaor other heart valves.

I

4. Patients with moderate AS undergoing coronary arterybypass surgery or surgery on the aorta or other heartvalves (see sections III.F. and VIII.D.).

IIa

5. Asymptomatic patients with severe AS and

● LV systolic dysfunction IIa

● Abnormal response to exercise (eg, hypotension) IIa

● Ventricular tachycardia IIb

● Marked or excessive LV hypertrophy (>15 mm) IIb

● Valve area <0.6 cm2 IIb

6. Prevention of sudden death in asymptomatic patientswith none of the findings listed under indication 5.

III

Aortic Balloon ValvotomyPercutaneous balloon aortic valvotomy has an important rolein treatment of adolescents and young adults with AS (seesection VI.A.) but a very limited role in older adults.Immediate hemodynamic results include a moderate reduc-tion in the transvalvular pressure gradient, but the postvalvot-

omy valve area is rarely.1.0 cm2. However, serious com-plications occur with a frequency of.10%, and restenosisand clinical deterioration occur within 6 to 12 months in mostpatients. Therefore, in adults with AS, balloon valvotomy isnot a substitute for AVR.

Balloon valvotomy can play a temporary role in themanagement of some symptomatic patients who are notinitially candidates for AVR. For example, patients withsevere AS and refractory pulmonary edema or cardiogenicshock may benefit from aortic valvuloplasty as a “bridge” tosurgery; an improved hemodynamic state may reduce therisks of AVR. Indications for palliative valvotomy in patientswith serious comorbid conditions are less well established,but most patients can expect temporary relief of symptomsdespite a very limited life expectancy. Asymptomatic patientswith severe AS who require urgent noncardiac surgery maybe candidates for valvotomy, but most such patients can besuccessfully treated with more conservative measures.

Recommendations for Aortic Balloon Valvotomy in Adults WithAortic Stenosis*

Indication Class

1. A “bridge” to surgery in hemodynamically unstablepatients who are at high risk for AVR.

IIa

2. Palliation in patients with serious comorbid conditions. IIb

3. Patients who require urgent noncardiac surgery. IIb

4. An alternative to AVR. III

*Recommendations for aortic balloon valvotomy in adolescents andyoung adults with AS are provided in section VI.A.

Special Considerations in the ElderlyBecause there is no effective medical therapy and balloonvalvotomy is not an acceptable alternative to surgery, AVRmust be considered in all elderly patients who have symptomscaused by AS. AVR is technically possible at any age, but thedecision to proceed with such surgery depends on manyfactors, including the patient’s wishes and expectations.

In addition to the confounding effects of CAD and thepotential for stroke, other considerations are specific to olderpatients. For example, a narrow LV outflow tract and smallaortic annulus sometimes present in elderly women may requireenlargement of the annulus. Heavy calcification of the valve,annulus, and aortic root may require debridement. Occasionally,a composite valve-aortic graft is needed. Excessive or inappro-priate hypertrophy associated with valvular stenosis can be amarker for perioperative morbidity and mortality. Preoperativerecognition of elderly patients with marked LV hypertrophyfollowed by appropriate perioperative management may sub-stantially reduce this morbidity and mortality.

B. Aortic Regurgitation

1. Acute Aortic RegurgitationIn acute severe aortic regurgitation (AR), the sudden largeregurgitant volume is imposed on a left ventricle of normalsize that has not had time to accommodate to the volumeoverload. LV end-diastolic and left atrial pressures mayincrease rapidly and dramatically. The Frank-Starling mech-anism is used, but the inability of the ventricle to develop




compensatory chamber dilatation acutely results in a decreasein forward stroke volume. Although tachycardia develops asa compensatory mechanism to maintain cardiac output, this isoften insufficient. Hence, patients frequently present withpulmonary edema and/or cardiogenic shock.

DiagnosisMany of the characteristic physical findings of chronic ARare modified or absent when valvular regurgitation is acute,which may lead to underestimation of its severity. Echocar-diography is indispensable in confirming the presence andseverity of valvular regurgitation, determining its etiology,estimating the degree of pulmonary hypertension (if tricuspidregurgitation [TR] is present), and determining whether thereis rapid equilibration of aortic and LV diastolic pressure.Evidence for rapid pressure equilibration includes short ARdiastolic half-time (,300 ms), short mitral deceleration time(,150 ms), or premature closure of the mitral valve.

Acute AR caused by aortic root dissection is a surgicalemergency that requires prompt identification and manage-ment. Transesophageal echocardiography is indicated whenaortic dissection is suspected. If the diagnosis remains uncer-tain, cardiac catheterization and aortography should be per-formed. Coronary angiography is an important component ofthe evaluation of aortic dissection and acute AR and shouldbe performed, provided that it does not delay urgent surgery.

TreatmentDeath from pulmonary edema, ventricular arrhythmias, elec-tromechanical dissociation, or circulatory collapse is commonin acute severe AR, even with intensive medical manage-ment. Early surgical intervention is recommended. Nitroprus-side and possibly inotropic agents such as dopamine ordobutamine to augment forward flow and reduce LV end-di-astolic pressure may be helpful to treat the patient temporarilybefore surgery. Intra-aortic balloon counterpulsation is con-traindicated. Althoughb-blockers are often used in treatingaortic dissection, they should be used cautiously, if at all, inthe setting of acute AR because they will block compensatorytachycardia.

2. Chronic Aortic RegurgitationChronic AR represents a condition of combined volumeoverload and pressure overload. As the disease progresses,recruitment of preload reserve and compensatory hypertrophypermit the ventricle to maintain normal ejection performancedespite the elevated afterload. The majority of patients remainasymptomatic throughout this compensated phase, whichmay last for decades. Vasodilator therapy has the potential toreduce the hemodynamic burden in such patients.

For the purposes of subsequent discussion, patients withnormal LV systolic function are defined as those with normalLV ejection fraction at rest. It is recognized that overall LVfunction is usually not “normal” in chronic severe AR andthat the hemodynamic abnormalities noted above may beconsiderable. It is also recognized that the transition to LVsystolic dysfunction represents a continuum and that nosingle hemodynamic measurement represents the absoluteboundary between normal LV systolic function and LVsystolic dysfunction.

The balance between afterload excess, preload reserve, andhypertrophy cannot be maintained indefinitely in many pa-tients, and afterload mismatch and/or depressed contractilityultimately result in a reduction in ejection fraction, first intothe low normal range and then below normal. At this point inthe natural history, patients often develop dyspnea, which isrelated to declining systolic function or elevated fillingpressures. However, this transition may be much moreinsidious, and it is possible for patients to remain asymptom-atic until severe LV dysfunction has developed.

LV systolic dysfunction (defined as an ejection fractionbelow normal at rest) is initially a reversible phenomenonpredominantly related to afterload excess, and full recoveryof LV size and function is possible with AVR. With time,during which the ventricle develops progressive chamberenlargement and a more spherical geometry, depressed myo-cardial contractility predominates over excessive loading asthe cause of progressive systolic dysfunction. This canprogress to the extent that the full benefit of surgicalcorrection of the regurgitant lesion in terms of recovery of LVfunction and improved survival can no longer be achieved.

A large number of studies have identified LV systolicfunction and end-systolic size as the most important determi-nants of survival and postoperative LV function in patientsundergoing AVR for chronic AR.

Several factors are associated with worse functional andsurvival results after AVR for chronic AR in patients withpreoperative LV systolic dysfunction. These include severityof symptoms, the severity of LV systolic dysfunction, and theduration of preoperative systolic dysfunction. Taken together,these observations support the recommendation that patientswith evidence of LV systolic dysfunction, even if asymptom-atic or minimally symptomatic, should undergo AVR beforemore severe symptoms or more severe ventricular dysfunc-tion develop.

Natural History

1. Asymptomatic Patients With Normal Left VentricularFunction.The current recommendations are derived from 7published series involving a total of 490 patients with a meanfollow-up period of 6.4 years. The rate of progression tosymptoms and/or LV systolic dysfunction averaged 4.3% peryear. Sudden death occurred in 6 of the 490 patients, anaverage mortality rate of,0.2% per year. Six of the 7 studiesreported the rate of development of asymptomatic LV dys-function; 36 of a total of 463 patients developed depressedsystolic function at rest without symptoms during a mean5.9-year follow-up period, a rate of 1.3% per year.

2. Asymptomatic Patients With Depressed Systolic Function.The limited data in asymptomatic patients with depressed LVejection fraction indicate that the majority develop symptomswarranting surgery within 2 to 3 years. The average rate ofsymptom onset in such patients is.25% per year.

3. Symptomatic Patients.There are no recent large-scalestudies of the natural history of symptomatic patients withchronic AR, because the onset of angina or significantdyspnea is usually an indication for valve replacement. Datafrom the presurgical era indicate that symptomatic patientshave a poor outcome with medical therapy, which is analo-




gous to that of patients with symptomatic AS, with mortalityrates of.10% per year in patients with angina pectoris and.20% per year in those with heart failure.

Diagnosis and Initial Evaluation of theAsymptomatic PatientThe diagnosis of chronic severe AR can usually be made on thebasis of physical examination. The chest x-ray and ECG arehelpful in evaluating overall heart size and rhythm, evidence ofLV hypertrophy, and evidence of conduction disorders.

Echocardiography is indicated to confirm the diagnosis ofAR if there is an equivocal diagnosis based on physicalexamination; assess the cause of AR as well as valvemorphology; provide a semiquantitative estimate of severityof regurgitation; assess LV dimension, mass, and systolicfunction; and assess aortic root size. In asymptomatic patientswith preserved systolic function, these initial measurementsrepresent the baseline information with which future serialmeasurements can be compared.

Recommendations for Echocardiography in Aortic Regurgitation

Indication Class

1. Confirm presence and severity of acute AR. I

2. Diagnosis of chronic AR in patients with equivocalphysical findings.

I

3. Assessment of etiology of regurgitation (including valvemorphology and aortic root size and morphology).

I

4. Assessment of LV hypertrophy, dimension (or volume),and systolic function.

I

5. Semiquantitative estimate of severity of AR. I

6. Reevaluation of patients with mild, moderate, or severeregurgitation with new or changing symptoms.

I

7. Reevaluation of LV size and function in asymptomaticpatients with severe regurgitation.

I

8. Reevaluation of asymptomatic patients with mild,moderate, or severe regurgitation and enlarged aorticroot.

I

9. Yearly reevaluation of asymptomatic patients with mildto moderate regurgitation with stable physical signs andnormal or near-normal LV chamber size.

III

If the patient is asymptomatic and leads an activelifestyle and the echocardiogram is of good quality, noother testing is necessary. If the patient has severe AR andis sedentary or has equivocal symptoms, exercise testing ishelpful to assess functional capacity, symptomatic re-sponses, and hemodynamic effects of exercise. If theechocardiogram is of insufficient quality to assess LVfunction, radionuclide angiography should be used inasymptomatic patients to measure LV ejection fraction atrest and estimate LV volumes. When patients are symp-tomatic on initial evaluation, it is reasonable to proceeddirectly with cardiac catheterization and angiography if theechocardiogram is of insufficient quality to assess LVfunction or severity of AR.

The exercise ejection fraction and change in ejectionfraction from rest to exercise are often abnormal, even inasymptomatic patients. However, these have not beenproved to have independent diagnostic or prognostic value

when LV function at rest and severity of LV volumeoverload by echocardiography are already known.

Recommendations for Exercise Testing in ChronicAortic Regurgitation*

Indication Class

1. Assessment of functional capacity and symptomaticresponses in patients with a history of equivocalsymptoms.

I

2. Evaluation of symptoms and functional capacity beforeparticipation in athletic activities.

IIa

3. Prognostic assessment before AVR in patients with LVdysfunction.

IIa

4. Exercise hemodynamic measurements to determine theeffect of AR on LV function.

IIb

5. Exercise radionuclide angiography for assessing LVfunction in asymptomatic or symptomatic patients.

IIb

6. Exercise echocardiography or dobutamine stressechocardiography for assessing LV function inasymptomatic or symptomatic patients.

III

*These recommendations differ from the ACC/AHA Guidelines forExercise Testing.3 The committee believes that indications 1, 2, and 3above warrant a higher recommendation than IIb.

Recommendations for Radionuclide Angiography inAortic Regurgitation

Indication Class

1. Initial and serial assessment of LV volume and functionat rest in patients with suboptimal echocardiograms orequivocal echocardiographic data.*

I

2. Serial assessment of LV volume and function at restwhen serial echocardiograms are not used.*

I

3. Assessment of LV volume and function in asymptomaticpatients with moderate to severe regurgitation whenechocardiographic evidence of declining LV function issuggestive but not definitive.*

I

4. Confirmation of subnormal LV ejection fraction beforerecommending surgery in an asymptomatic patient withborderline echocardiographic evidence of LVdysfunction.*

I

5. Assessment of LV volume and function in patients withmoderate to severe regurgitation when clinicalassessment and echocardiographic data arediscordant.*

I

6. Routine assessment of exercise ejection fraction. IIb

7. Quantification of AR in patients with unsatisfactoryechocardiograms.

IIb

8. Quantification of AR in patients with satisfactoryechocardiograms.

III

9. Initial and serial assessment of LV volume and functionat rest in addition to echocardiography.

III

*In centers with expertise in cardiac magnetic resonance imaging(MRI), cardiac MRI may be used in place of radionuclide angiography forthese indications.

Asymptomatic patients with normal LV systolic functionmay participate in all forms of normal daily physical activity,including mild-intensity forms of exercise and in some casescompetitive athletics. Isometric exercise should be avoided.Recommendations for participation in competitive athletics




were published by the Task Force on Acquired ValvularHeart Disease of the 26th Bethesda Conference.7

Medical TherapyTherapy with vasodilating agents is designed to improveforward stroke volume and reduce regurgitant volume. Theseeffects should translate into reductions in LV end-diastolicvolume, wall stress, and afterload, resulting in preservation ofLV systolic function and reduction in LV mass. These effectshave been observed in small numbers of patients whoreceived oral therapy with hydralazine and nifedipine for 1 to2 years. Less consistent results have been reported withangiotensin converting enzyme (ACE) inhibitors, dependingon the degree of reduction in arterial pressure and end-dia-stolic volume.

Only 1 study, in which long-acting nifedipine was com-pared with digoxin therapy in 143 patients followed up for 6years, has evaluated whether vasodilating therapy alters thelong-term natural history of chronic asymptomatic AR in afavorable manner. Over 6 years, long-acting nifedipine re-duced the need for valve replacement from 34% to 15%.Moreover, when patients who received nifedipine did un-dergo AVR because of symptoms or impaired systolic func-tion, all survived surgery, and LV size and function improvedconsiderably in all patients.

The goal of vasodilator therapy is to reduce systolic bloodpressure. Drug dosage should be increased until there is ameasurable decrease in systolic blood pressure or the patientdevelops side effects. It is rarely possible to decrease systolicblood pressure to normal because of the increased LV strokevolume, and drug dosage should not be increased excessivelyin an attempt to achieve this goal. Vasodilator therapy is ofunknown benefit and is not indicated in patients with normalblood pressure and/or normal cavity size.

Vasodilator therapy is not recommended for asymptom-atic patients with mild AR and normal LV function in theabsence of systemic hypertension, as these patients have anexcellent outcome with no therapy. Vasodilator therapy isnot an alternative to surgery for asymptomatic or symp-tomatic patients with severe AR and LV systolic dysfunc-tion. Whether symptomatic patients who have preservedsystolic function can be safely treated with aggressivemedical management and whether aggressive medicalmanagement is as good or better than AVR have not beendetermined. It is recommended that symptomatic patientsundergo surgery rather than long-term medical therapy.

Recommendations for Vasodilator Therapy for ChronicAortic Regurgitation

Indication Class

1. Chronic therapy in patients with severe regurgitationwho have symptoms and/or LV dysfunction whensurgery is not recommended because of additionalcardiac or noncardiac factors.

I

2. Long-term therapy in asymptomatic patients withsevere regurgitation who have LV dilatation butnormal systolic function.

I

3. Long-term therapy in asymptomatic patients withhypertension and any degree of regurgitation.

I

Indication Class

4. Long-term ACE inhibitor therapy in patients withpersistent LV systolic dysfunction after AVR.

I

5. Short-term therapy to improve the hemodynamicprofile of patients with severe heart failuresymptoms and severe LV dysfunction beforeproceeding with AVR.

I

6. Long-term therapy in asymptomatic patients withmild to moderate AR and normal LV systolic function.

III

7. Long-term therapy in asymptomatic patients with LVsystolic dysfunction who are otherwise candidatesfor valve replacement.

III

8. Long-term therapy in symptomatic patients witheither normal LV function or mild to moderate LVsystolic dysfunction who are otherwise candidatesfor valve replacement.

III

Serial TestingIn general, the stability and chronicity of the regurgitantlesion and the LV response to the volume load must beestablished when the patient first presents to the physician,especially if AR is moderate to severe. If the chronic natureof the lesion is uncertain and the patient does not presentinitially with 1 or more indications for surgery, the physicalexamination and echocardiogram should be repeated 2 to 3months after the initial evaluation to ensure that a subacuteprocess with rapid progression is not under way. Once thechronicity and stability of the process have been established,the frequency of clinical reevaluation and repeat noninvasivetesting depends on severity of valvular regurgitation, degreeof LV dilatation, level of systolic function, and whetherprevious serial studies have revealed progressive changes inLV size or function. In most patients, serial testing during thelong-term follow-up period should include a detailed history,physical examination, and echocardiography. Serial chestx-rays and ECGs are of less value but are helpful in selectedpatients.

Asymptomatic patients with mild AR, little or no LVdilatation, and normal LV systolic function can be seen on ayearly basis with instructions to alert the physician if symp-toms develop in the interim. Yearly echocardiography is notnecessary unless there is clinical evidence that regurgitationhas worsened. Routine echocardiography can be performedevery 2 to 3 years in such patients.

Asymptomatic patients with normal systolic function butsevere AR and significant LV dilatation (end-diastolic dimen-sion .60 mm) require more frequent and careful reevalua-tion, with a history and physical examination every 6 monthsand echocardiography every 6 to 12 months, depending onseverity of dilatation and stability of measurements. If thepatient’s condition is stable, echocardiographic measure-ments are not required more frequently than every 12 months.It is reasonable to obtain serial echocardiograms as often asevery 4 to 6 months in patients with more advanced LVdilatation (end-diastolic dimension.70 mm or end-systolicdimension .50 mm) for whom the risk of developingsymptoms or LV dysfunction ranges from 10% to 20% per




year. Serial chest x-rays and ECGs are of less value but arehelpful in selected patients.

Chronic AR may develop from disease processes involvingthe proximal ascending aorta. In patients with aortic rootdilatation, serial echocardiograms are indicated to evaluateaortic root size as well as LV size and function.

Repeat echocardiograms are also recommended when thepatient has onset of symptoms, there is an equivocal historyof changing symptoms or exercise tolerance, or there areclinical findings suggesting worsening regurgitation or pro-gressive LV dilatation. Patients with echocardiographic evi-dence of progressive ventricular dilatation or declining sys-tolic function have a greater likelihood of developingsymptoms or LV dysfunction and should have more frequentfollow-up examinations (every 6 months) than those withstable LV function.

In some centers with expertise in nuclear cardiology, serialradionuclide ventriculography to assess LV volume andfunction at rest may be an accurate and cost-effective alter-native to serial echocardiography. However, there is nojustification for routine serial testing with both echocardiog-raphy and radionuclide ventriculography. Serial radionuclideventriculograms are also recommended in patients with sub-optimal echocardiograms and when there is a discrepancybetween clinical assessment and echocardiographic data. Incenters with specific expertise in cardiac MRI, serial MRImay be performed in place of radionuclide angiography forthe indications listed above.

Indications for Cardiac CatheterizationCardiac catheterization is not required in patients withchronic AR unless there are questions about the severity ofAR, hemodynamic abnormalities, or LV systolic dysfunctiondespite physical examination and noninvasive testing orunless AVR is contemplated and there is a need to assesscoronary anatomy (see section VIII).

Recommendations for Cardiac Catheterization in ChronicAortic Regurgitation

Indication Class

1. Coronary angiography before AVR in patients at riskfor CAD (see section VIII.B.).

I

2. Assessing severity of regurgitation whennoninvasive tests are inconclusive or discordantwith clinical findings regarding severity ofregurgitation or need for surgery.

I

3. Assessing LV function when noninvasive tests areinconclusive or discordant with clinical findingsregarding LV dysfunction and need for surgery inpatients with severe AR.

I

4. Assessment of LV function and severity ofregurgitation before AVR when noninvasive tests areadequate and concordant with clinical findings andcoronary angiography is not needed.

IIb

5. Assessment of LV function and severity ofregurgitation in asymptomatic patients whennoninvasive tests are adequate.

III

Hemodynamic and angiographic assessment of severity ofAR and LV function may be necessary in some patients being

considered for surgery when there are conflicting data be-tween clinical assessment and noninvasive tests. Hemody-namic measurements during exercise are occasionally helpfulin determining the effect of AR on LV function or in makingdecisions about medical or surgical therapy. In selectedpatients with severe AR, borderline or normal LV systolicfunction, and LV chamber enlargement that is approachingthe threshold for operation (defined below), measurement ofcardiac output and LV filling pressures at rest and duringexercise with a right-heart catheter may be valuable foridentifying patients with severe hemodynamic abnormalitiesin whom surgery is warranted.

Indications for Aortic Valve ReplacementIn patients with pure chronic AR, AVR should be consideredonly if AR is severe. Patients with only mild AR are notcandidates for valve replacement, and if they have symptomsor LV dysfunction, other causes should be considered, suchas CAD, hypertension, or cardiomyopathic processes. Thefollowing discussion applies only to those patients with puresevere AR.

1. Symptomatic Patients With Normal Left Ventricular Sys-tolic Function.AVR is indicated in patients with normalsystolic function (defined as ejection fraction$0.50 at rest)who have New York Heart Association (NYHA) functionalClass III or IV symptoms or Canadian Heart Associationfunctional Class II to IV angina pectoris. In many patientswith NYHA functional Class II dyspnea, the cause of symp-toms is often unclear, and it may be difficult to differentiatethe effects of deconditioning or aging from true cardiacsymptoms. In such patients, exercise testing may be valuable.If the cause of these mild symptoms is uncertain and if theyare not severe enough to interfere with the patient’s lifestyle,a period of observation may be reasonable. However, newonset of mild dyspnea has different implications in severeAR, especially in patients with increasing LV chamber size orevidence of declining LV systolic function into the lownormal range. Mild symptoms are an indication for AVR insuch patients.

2. Symptomatic Patients With Left Ventricular Dysfunction.Patients with NYHA functional Class II, III, or IV symptomsand mild to moderate LV systolic dysfunction (ejectionfraction 0.25 to 0.49) should undergo AVR. Patients withfunctional Class IV symptoms have worse postoperativesurvival rates and lower likelihood of recovery of systolicfunction than patients with less severe symptoms, but AVRwill improve ventricular loading conditions and expeditesubsequent management of LV dysfunction. Symptomaticpatients with advanced LV dysfunction (ejection fraction,0.25 and/or end-systolic dimension.60 mm) presentdifficult management issues, as many have developed irre-versible myocardial changes. AVR should be more stronglyconsidered in patients with NYHA functional Class II and IIIsymptoms, especially if (1) symptoms and evidence of LVdysfunction are of recent onset and (2) intensive short-termtherapy with vasodilators, diuretics, and/or intravenous pos-itive inotropic agents results in substantial improvement inhemodynamics or systolic function. However, even in pa-




tients with NYHA functional Class IV symptoms and ejectionfraction ,0.25, the high risks associated with AVR andsubsequent medical management of LV dysfunction areusually a better alternative than the higher risks of long-termmedical management alone.

3. Asymptomatic Patients.AVR in asymptomatic patients re-mains a controversial topic, but it is generally agreed that valvereplacement is indicated in patients with LV systolic dysfunction.As noted previously, for the purposes of these guidelines, LVsystolic dysfunction is defined as an ejection fraction below normalat rest, ie,#0.50. It is recognized that this lower limit is techniquedependent and may vary among institutions.Valve replacementis also recommended in patients with severe LV dilatation(end-diastolic dimension.75 mm or end-systolic dimension.55 mm), even if ejection fraction is normal. Such patientsappear to represent a high-risk group with an increasedincidence of sudden death, and thus far the results of valvereplacement have been excellent. In contrast, postoperativemortality is considerable once patients with severe LVdilatation develop symptoms and/or LV systolic dysfunction.

Women tend to develop symptoms and/or LV dysfunctionwith less LV dilatation than men; this appears to be related tobody size, as these differences are not apparent when LVdimensions are corrected for body surface area. Hence, LVdimensions alone may be misleading in small patients ofeither gender, and the threshold values of end-diastolic andend-systolic dimension recommended for AVR in asymptom-atic patients (75 mm and 55 mm, respectively) may need to bereduced for such patients. There are no data from which toderive guidelines for LV dimensions corrected for body size,and clinical judgment is required.

Recommendations for Aortic Valve Replacement in ChronicSevere Aortic Regurgitation

Indication Class

1. Patients with NYHA functional Class III or IV symptomsand preserved LV systolic function, defined as normalejection fraction at rest (ejection fraction >0.50).

I

2. Patients with NYHA functional Class II symptoms andpreserved LV systolic function (ejection fraction >0.50at rest) but with progressive LV dilatation or decliningejection fraction at rest on serial studies or decliningeffort tolerance on exercise testing.

I

3. Patients with Canadian Heart Association functionalClass II or greater angina with or without CAD.

I

4. Asymptomatic or symptomatic patients with mild tomoderate LV dysfunction at rest (ejection fraction 0.25to 0.49).

I

5. Patients undergoing coronary artery bypass surgery orsurgery on the aorta or other heart valves.

I

6. Patients with NYHA functional Class II symptoms andpreserved LV systolic function (ejection fraction >0.50at rest) with stable LV size and systolic function onserial studies and stable exercise tolerance.

IIa

7. Asymptomatic patients with normal LV systolicfunction (ejection fraction >0.50) but with severe LVdilatation (end-diastolic dimension >75 mm orend-systolic dimension >55 mm).*

IIa

Indication Class

8. Patients with severe LV dysfunction (ejection fraction<0.25).

IIb

9. Asymptomatic patients with normal systolic functionat rest (ejection fraction >0.50) and progressive LVdilatation when the degree of dilatation is moderatelysevere (end-diastolic dimension 70 to 75 mm,end-systolic dimension 50 to 55 mm).

IIb

10. Asymptomatic patients with normal systolic functionat rest (ejection fraction >0.50) but with decline inejection fraction during

III

● Exercise radionuclide angiography IIb

● Stress echocardiography III

11. Asymptomatic patients with normal systolic functionat rest (ejection fraction >0.50) and LV dilatationwhen degree of dilatation is not severe (end-diastolicdimension <70 mm, end-systolic dimension <50 mm).

III

*Consider lower threshold values for patients of small stature of eithergender. Clinical judgment is required.

Concomitant Aortic Root DiseaseIn addition to causing acute AR, diseases of the proximalaorta may also contribute to chronic AR. If AR is mild and/orthe left ventricle is only mildly dilated, management shouldfocus on treating the underlying aortic root disease, which isbeyond the scope of these guidelines. However, in manypatients, AR may be severe, in which case decisions aboutmedical therapy and timing of surgery must take into accountboth conditions. In general, AVR and aortic root reconstruc-tion are indicated in patients with disease of the proximalaorta and AR of any severity when the degree of aortic rootdilatation is$50 mm by echocardiography.

Evaluation of Patients After Aortic Valve ReplacementAfter AVR, careful follow-up is necessary during the earlyand long-term postoperative course to evaluate prostheticvalve function and assess LV function, as discussed in detailin section VII.C. An echocardiogram should be performedsoon after surgery to assess the results of surgery on LV sizeand function and to serve as a baseline for comparison ofsubsequent echocardiograms. In the first few weeks aftersurgery, there is little change in LV systolic function, andejection fraction may deteriorate, compared with preoperativevalues, because of the reduced preload. A better predictor ofsubsequent LV systolic function is the reduction in LVend-diastolic dimension, which declines significantly withinthe first week or two of operation. This is an excellent markerof the functional success of AVR, as the magnitude of earlyreduction in end-diastolic dimension after operation corre-lates with the magnitude of late increase in ejection fraction.

Patients with persistent LV dilatation on the initial postop-erative echocardiogram should receive the same treatment,including ACE inhibitors, as any other patient with symp-tomatic or asymptomatic LV dysfunction.

C. Mitral StenosisThe normal mitral valve area is 4.0 to 5.0 cm2. Narrowing ofthe valve area to,2.5 cm2 must occur before development ofsymptoms.




A mitral valve area.1.5 cm2 usually does not producesymptoms at rest. However, if there is an increase intransmitral flow or a decrease in the diastolic filling period,there will be a rise in left atrial pressure and development ofsymptoms. Thus, the first symptoms of dyspnea in patientswith mild MS are usually precipitated by exercise, emotionalstress, infection, pregnancy, or atrial fibrillation with a rapidventricular response.

Natural HistoryMS is a continuous, progressive, lifelong disease, usuallyconsisting of a slow, stable course in the early years andprogressive acceleration later in life. In developed countries,there is a long latent period of 20 to 40 years from theoccurrence of rheumatic fever to onset of symptoms. Oncesymptoms develop, there is another period of almost a decadebefore symptoms become disabling. Overall, the 10-yearsurvival of untreated patients with MS is 50% to 60%,depending on symptoms at presentation. In the asymptomaticor minimally symptomatic patient, survival is.80% at 10years, with 60% of patients having no progression of symp-toms. However, once significant limiting symptoms occur,there is a dismal 10-year survival rate of 0% to 15%, andwhen there is severe pulmonary hypertension, mean survivaldrops to,3 years. Mortality of untreated patients with MS iscaused by progressive heart failure in 60% to 70%, systemicembolism in 20% to 30%, pulmonary embolism in 10%, andinfection in 1% to 5%.

Evaluation and Management of the Asymptomatic PatientThe diagnosis of MS should be based on the history, physicalexamination, chest x-ray, and ECG. The diagnostic tool ofchoice in the evaluation of a patient with MS is 2-D and Dopplerechocardiography. The morphological appearance of the mitralvalve apparatus should be assessed by 2-D echocardiography,including leaflet mobility, leaflet thickness, leaflet calcification,subvalvular fusion, and appearance of the commissures. Thesefeatures may be important when considering the timing and typeof intervention to be performed. Chamber size and function aswell as other structural valvular, myocardial, or pericardialabnormalities should also be assessed.

The hemodynamic severity of the obstruction should beassessed with Doppler echocardiography. The mean transmitralgradient can be accurately and reproducibly measured from thecontinuous wave Doppler signal across the mitral valve with themodified Bernoulli equation, and the mitral valve area can benoninvasively measured by either the diastolic half-time methodor the continuity equation. The half-time method may beinaccurate in patients with abnormalities of left atrial or LVcompliance, those with associated AR, and those with previousmitral valvotomy. Doppler echocardiography should also beused when possible to estimate pulmonary artery systolic pres-sure from the TR velocity signal and assess severity of concom-itant MR or AR. Formal hemodynamic exercise testing can bedone noninvasively by either a supine bicycle or upright tread-mill with Doppler recordings of transmitral and tricuspid veloc-ities. This allows measurement of both the transmitral gradientand pulmonary artery systolic pressure at rest and with exercise.Dobutamine stress testing with Doppler recordings may also beperformed.

Recommendations for Echocardiography in Mitral Stenosis

Indication Class

1. Diagnosis of MS, assessment of hemodynamicseverity (mean gradient, mitral valve area,pulmonary artery pressure), and assessment of rightventricular size and function.

I

2. Assessment of valve morphology to determinesuitability for percutaneous mitral balloonvalvotomy.

I

3. Diagnosis and assessment of concomitant valvularlesions.

I

4. Reevaluation of patients with known MS withchanging symptoms or signs.

I

5. Assessment of hemodynamic response of meangradient and pulmonary artery pressures by exerciseDoppler echocardiography in patients when there isa discrepancy between resting hemodynamics andclinical findings.

IIa

6. Reevaluation of asymptomatic patients withmoderate to severe MS to assess pulmonary arterypressure.

IIb

7. Routine reevaluation of the asymptomatic patientwith mild MS and stable clinical findings.

III

Recommendations for Transesophageal Echocardiography inMitral Stenosis

Indication Class

1. Assess for presence or absence of left atrial thrombusin patients being considered for percutaneous mitralballoon valvotomy or cardioversion.

IIa

2. Evaluate mitral valve morphology and hemodynamicswhen transthoracic echocardiography providessuboptimal data.

IIa

3. Routine evaluation of mitral valve morphology andhemodynamics when complete transthoracicechocardiographic data are satisfactory.

III

In the asymptomatic patient who has documented mild MS(valve area.1.5 cm2 and mean gradient,5 mm Hg), nofurther evaluation is needed on the initial workup. Thesepatients usually remain stable for many years. If MS is moresignificant, further evaluation should be considered if themitral valve morphology appears to be suitable for mitralvalvotomy with pliable, noncalcified valves with little or nosubvalvular fusion and no calcification in the commissures.Patients with moderate pulmonary hypertension at rest (pul-monary artery systolic pressure.50 mm Hg) and pliablemitral valve leaflets may be considered for percutaneousmitral valvotomy even if they deny symptoms. In patientswho lead a sedentary lifestyle, a hemodynamic exercise testwith Doppler echocardiography is useful. Objective limita-tion of exercise tolerance with a rise in transmitral gradient.15 mm Hg and pulmonary artery systolic pressure.60 mm Hg may be an indication to consider percutaneousvalvotomy if mitral valve morphology is suitable.

All patients should be informed that any change in symp-toms warrants reevaluation. In the asymptomatic patient,yearly reevaluation is recommended; at this time, a history,physical examination, chest x-ray, and ECG should be ob-




tained. A yearly echocardiogram is not recommended unlessthere is a change in clinical status. Ambulatory ECG moni-toring to detect paroxysmal atrial fibrillation is indicated inpatients with palpitations.

Medical Therapy

1. General Principles.Because MS is primarily caused byrheumatic fever, prophylaxis against rheumatic fever is rec-ommended. Appropriate endocarditis prophylaxis is alsorecommended. Patients who have more than a mild degree ofMS should be counseled to avoid unusual physical stresses.Agents with negative chronotropic properties, such asb-blockers or calcium channel blockers, may be of benefit inpatients with sinus rhythm who have exertional symptoms ifthe symptoms occur with high heart rates. Salt restriction andintermittent administration of a diuretic are useful if there isevidence of pulmonary vascular congestion. Digitalis doesnot benefit patients with MS in sinus rhythm unless there isleft and/or right ventricular dysfunction.

2. Atrial Fibrillation. Atrial fibrillation develops in 30% to40% of patients with symptomatic MS. Significant hemody-namic consequences may result from acute development ofatrial fibrillation, with loss of atrial contribution to LV filling,and from the rapid ventricular rate. Atrial fibrillation occursmore commonly in older patients and is associated with apoorer prognosis, with a 10-year survival rate of 25%compared with 46% in patients who remain in sinus rhythm.The risk of arterial embolization, especially stroke, is signif-icantly increased in patients with atrial fibrillation. Treatmentof an acute episode of rapid atrial fibrillation consists ofanticoagulation with heparin and control of the heart rateresponse. Intravenous digoxin, calcium channel blockers, orb-blockers should be used to control ventricular response. Ifthere is hemodynamic instability, electrical cardioversionshould be undertaken urgently, with intravenous heparinbefore, during, and after the procedure. Patients who havebeen in atrial fibrillation.24 to 48 hours without anticoag-ulation are at an increased risk for embolic events aftercardioversion, but patients may also have an embolic eventwith ,24 hours of atrial fibrillation. The decision to proceedwith elective cardioversion depends on multiple factors,including duration of atrial fibrillation, hemodynamic re-sponse to onset of atrial fibrillation, documented history ofprior episodes of atrial fibrillation, and history of priorembolic events. If the decision has been made to proceed withelective cardioversion in a patient who has had documentedatrial fibrillation for .24 to 48 hours and who has not beenon long-term anticoagulation, 1 of 2 approaches is recom-mended, based on data from patients with nonrheumatic atrialfibrillation. The first is anticoagulation with warfarin for$3weeks, followed by elective cardioversion. The second isanticoagulation with heparin and transesophageal echocardi-ography to look for left atrial thrombus. In the absence of leftatrial thrombus, cardioversion is performed with intravenousheparin before, during, and after the procedure. It is importantto continue anticoagulation after cardioversion to preventthrombus formation caused by atrial mechanical inactivityand to then maintain the patient on long-term warfarin unlessthere is a strong contraindication to anticoagulation. Contro-versy surrounds whether percutaneous mitral valvotomyshould be performed in patients with new-onset atrial fibril-lation and moderate to severe MS who are otherwiseasymptomatic.

3. Prevention of Systemic Embolization.Systemic emboliza-tion may occur in 10% to 20% of patients with MS. The riskof embolization is related to age, the presence of atrialfibrillation, and history of previous embolic events. One thirdof embolic events occur#1 month after onset of atrialfibrillation, and two thirds occur within 1 year. The frequencyof embolic events does not seem to be related to severity ofMS, cardiac output, size of left atrium, or presence ofsymptoms. An embolic event may thus be the initial mani-festation of MS. In patients who have experienced an embolicevent, the frequency of recurrence is as high as 15 to 40events per 100 patient months. There are no data to supportthe concept that oral anticoagulation is beneficial in patientswith MS who have not had atrial fibrillation or an embolicevent. It is controversial whether patients who have not hadatrial fibrillation or an embolic event and who might be athigher risk for future embolic events (ie, severe stenosis orenlarged left atrium) should be considered for long-termwarfarin therapy.

Recommendations for Anticoagulation in Mitral Stenosis

Indication Class

1. Patients with atrial fibrillation, paroxysmal or chronic. I

2. Patients with a prior embolic event. I

3. Patients with severe MS and left atrial dimension>55 mm by echocardiography.*

IIb

4. All other patients with MS. III

*Based on a grade C recommendation given this indication byAmerican College of Chest Physicians Fourth Consensus Conference onAntithrombotic Therapy. The Working Group of the European Society ofCardiology recommended a lower threshold of left atrial dimension(>50 mm) for recommending anticoagulation.

Physical Activity and ExerciseThe 26th Bethesda Conference on Recommendations forDetermining Eligibility for Competition in Athletes WithCardiovascular Abnormalities has published guidelines forpatients with MS who wish to engage in competitiveathletics.7

Evaluation of the Symptomatic PatientPatients who develop symptoms should undergo evaluationwith a history, physical examination, ECG, chest x-ray, andechocardiography to evaluate mitral valve morphology, mi-tral valve hemodynamics, and pulmonary artery pressure.Patients with NYHA functional Class II symptoms andmoderate or severe stenosis (mitral valve area#1.5 cm2 ormean gradient$5 mm Hg) may be considered for mitralballoon valvotomy if they have suitable mitral valve mor-phology. Patients with NYHA functional Class III or IVsymptoms and evidence of severe MS have a poor prognosisif left untreated, and intervention with either balloon valvot-omy or surgery should be considered.

A subset of patients have significant limiting symptoms yetresting hemodynamics that do not indicate moderate to severeMS. If there is a discrepancy between symptoms and hemo-dynamic data, formal exercise testing or dobutamine stresstesting may be useful to differentiate symptoms caused byMS from other causes. Exercise tolerance, heart rate andblood pressure response, transmitral gradient, and pulmonaryartery pressure can be obtained at rest and during exercise.




This can usually be accomplished by either supine bicycle orupright exercise with Doppler recording of TR and transmi-tral velocities. Right- and left-heart catheterization withexercise may also be helpful. Patients who are symptomaticwith a significant elevation of pulmonary artery pressure(.60 mm Hg), mean transmitral gradient (.15 mm Hg), orpulmonary artery wedge pressure ($25 mm Hg) on exertionhave hemodynamically significant MS and should be consid-ered for further intervention. Alternatively, patients who donot manifest elevation in pulmonary artery, pulmonary arterywedge, or transmitral pressures coincident with developmentof exertional symptoms most likely would not benefit fromintervention on the mitral valve.

Indications for Cardiac CatheterizationIn most instances, Doppler measurements of transmitralgradient, valve area, and pulmonary pressure correlate wellwith each other. Catheterization is indicated to assess hemo-dynamics when there is a discrepancy between Doppler-derived hemodynamics and the clinical status of a symptom-atic patient. Absolute left- and right-sided pressuremeasurements should be obtained by catheterization whenthere is elevation of pulmonary artery pressure out of propor-tion to mean gradient and valve area. Catheterization includ-ing left ventriculography (to evaluate severity of MR) isindicated when there is a discrepancy between Doppler-derived mean gradient and valve area. Coronary angiographymay be required in selected patients who may need toundergo intervention (see section VIII).

Recommendations for Cardiac Catheterization inMitral Stenosis

Indication Class

1. Perform percutaneous mitral balloon valvotomy inproperly selected patients.

I

2. Assess severity of MR in patients being considered forpercutaneous mitral balloon valvotomy when clinical andechocardiographic data are discordant.

IIa

3. Assess pulmonary artery, left atrial, and LV diastolicpressures when symptoms and/or estimated pulmonaryartery pressure are discordant with the severity of MS by2-D and Doppler echocardiography.

IIa

4. Assessment of hemodynamic response of pulmonaryartery and left atrial pressures to stress when clinicalsymptoms and resting hemodynamics are discordant.

IIa

5. Assessment of mitral valve hemodynamics when 2-D andDoppler echocardiographic data are concordant withclinical findings.

III

Indications for Surgical or Percutaneous ValvotomyWith the development of cardiopulmonary bypass in the1960s, open mitral commissurotomy and replacement of themitral valve became the surgical procedures of choice fortreatment of MS. Percutaneous mitral balloon valvotomyemerged in the mid 1980s. This procedure has become anaccepted alternative to surgical approaches in selected pa-tients. The procedure itself is technically challenging andinvolves a steep learning curve. There is a higher success rateand lower complication rate in experienced high-volume

centers. Thus, results of the procedure are highly dependenton the experience of the operators, which must be taken intoconsideration when making recommendations for proceedingwith this technique.

The immediate results of percutaneous mitral valvotomyare similar to those of mitral commissurotomy. The meanvalve area usually doubles (from 1.0 cm2 to 2.0 cm2), witha 50% to 60% reduction in transmitral gradient. Overall,80% to 95% of patients may have a successful procedure,which is defined as a mitral valve area.1.5 cm2 and adecrease in left atrial pressure to#18 mm Hg in theabsence of complications. The most common acute com-plications reported in large series include severe MR,which occurs in 2% to 10%, and a residual atrial septaldefect. A large atrial septal defect (.1.5:1 left-to-rightshunt) occurs in up to 12% of patients with the doubleballoon technique and in,5% with the Inoue balloontechnique. Smaller atrial septal defects may be detected bytransesophageal echocardiography in larger numbers ofpatients. Less frequent complications include perforationof the left ventricle (0.5% to 4.0%), embolic events (0.5%to 3%), and myocardial infarction (0.3% to 0.5%). Themortality for patients who undergo balloon valvotomy inlarger series has ranged from 1% to 2%; however, withincreasing experience in the procedure, percutaneous mi-tral valvotomy can be done in selected patients with amortality of ,1%.

Follow-up information after percutaneous balloon val-votomy is limited. Event-free survival (freedom fromdeath, repeat valvotomy, or mitral valve replacement)overall is 50% to 65% over 3 to 7 years, with an event-freesurvival of 80% to 90% in patients with favorable mitralvalve morphology. More than 90% of patients free ofevents remain in NYHA functional Class I or II afterpercutaneous mitral valvotomy. Randomized trials havecompared percutaneous balloon valvotomy with bothclosed and open surgical commissurotomy. There was nosignificant difference in acute hemodynamic results orcomplication rate between percutaneous mitral valvotomyand surgery, and early follow-up data indicate no differ-ence in hemodynamics, clinical improvement, or exercisetime. However, longer-term follow-up studies at 3 to 7years indicate more favorable hemodynamic and symptom-atic results with percutaneous balloon valvotomy than withclosed commissurotomy and results equivalent to those ofopen commissurotomy.

The immediate results, acute complications, and follow-upresults of percutaneous balloon valvotomy depend on multi-ple factors. It is of utmost importance that this procedure beperformed in centers with skilled, experienced operators.Other factors include age, NYHA functional class, severity ofstenosis, LV end-diastolic pressure, cardiac output, and pul-monary artery wedge pressure. The underlying mitral valvemorphology is the most important factor in determiningoutcome, and patients with valvular calcification, thickenedfibrotic leaflets with decreased mobility, and subvalvularfusion have a higher incidence of acute complications and ahigher rate of recurrent stenosis on follow-up. In patients withnoncalcified pliable valves and no calcium in the commis-




sures, the procedure can be performed with a high successrate (.90%), low complication rate (,2% to 3%), andsustained improvement in 80% to 90% over a 3- to 7-yearfollow-up period.

Relative contraindications to percutaneous balloon valvot-omy include the presence of a left atrial thrombus andsignificant (31to 41) MR. Transesophageal echocardiogra-phy is frequently performed before the procedure to deter-mine the presence of left atrial thrombus, specifically exam-ining the left atrial appendage. If a thrombus is found, 3months of anticoagulation with warfarin may result in reso-lution of the thrombus.

In centers with skilled, experienced operators, percuta-neous balloon valvotomy should be considered the initialprocedure of choice for symptomatic patients with moder-ate to severe MS who have a favorable valve morphologyin the absence of significant MR or a left atrial thrombus.In asymptomatic patients with a favorable valve morphol-ogy, percutaneous mitral valvotomy may be considered ifthere is evidence of a hemodynamic effect on left atrialpressure (new-onset atrial fibrillation) or pulmonary circu-lation (pulmonary artery pressure.50 mm Hg at rest or.60 mm Hg with exercise). The strength of evidence forthis recommendation is low because there are no datacomparing the results of percutaneous balloon valvotomyand medical therapy in such patients. It is controversialwhether severely symptomatic patients with less favorablevalve morphology should undergo this catheter-based pro-cedure. Although there is a higher acute complication rateand lower event-free survival (approximately 50% at 5years in these patients, compared with 80% to 90% inpatients with favorable valve morphology), this must beweighed against the risks and potential complications ofsurgical mitral valve replacement.

Recommendations for Percutaneous Mitral Balloon Valvotomy

Indication Class

1. Symptomatic patients (NYHA functional Class II, III, orIV), moderate or severe MS (mitral valve area <1.5cm2),* and valve morphology favorable forpercutaneous balloon valvotomy in the absence of leftatrial thrombus or moderate to severe MR.

I

2. Asymptomatic patients with moderate or severe MS(mitral valve area <1.5 cm2)* and valve morphologyfavorable for percutaneous balloon valvotomy whohave pulmonary hypertension (pulmonary arterysystolic pressure >50 mm Hg at rest or 60 mm Hgwith exercise) in the absence of left atrial thrombus ormoderate to severe MR.

IIa

3. Patients with NYHA functional Class III-IV symptoms,moderate or severe MS (mitral valve area <1.5 cm2),*and a nonpliable calcified valve who are at high riskfor surgery in the absence of left atrial thrombus ormoderate to severe MR.

IIa

4. Asymptomatic patients, moderate or severe MS (mitralvalve area <1.5 cm2),* and valve morphologyfavorable for percutaneous balloon valvotomy whohave new onset of atrial fibrillation in the absence ofleft atrial thrombus or moderate to severe MR.

IIb

Indication Class

5. Patients in NYHA functional Class III-IV, moderate orsevere MS (mitral valve area <1.5 cm2), and anonpliable calcified valve who are low-risk candidatesfor surgery.

IIb

6. Patients with mild MS. III

*The committee recognizes that there may be variability in themeasurement of mitral valve area and that the mean transmitral gradient,pulmonary artery wedge pressure, and pulmonary artery pressure at restor during exercise should also be taken into consideration.

Recommendations for Mitral Valve Repair for Mitral Stenosis

Indication Class

1. Patients with NYHA functional Class III-IV symptoms,moderate or severe MS (mitral valve area <1.5 cm2),*and valve morphology favorable for repair if percutaneousmitral balloon valvotomy is not available.

I

2. Patients with NYHA functional Class III-IV symptoms,moderate or severe MS (mitral valve area <1.5 cm2),*and valve morphology favorable for repair if a left atrialthrombus is present despite anticoagulation.

I

3. Patients with NYHA functional Class III-IV symptoms,moderate or severe MS (mitral valve area <1.5 cm2),*and a nonpliable or calcified valve with the decision toproceed with either repair or replacement made at thetime of the operation.

I

4. Patients in NYHA functional Class I, moderate or severeMS (mitral valve area <1.5 cm2),* and valve morphologyfavorable for repair who have had recurrent episodes ofembolic events on adequate anticoagulation.

IIb

5. Patients with NYHA functional Class I-IV symptoms andmild MS.

III

*The committee recognizes that there may be a variability in themeasurement of mitral valve area and that the mean transmitral gradient,pulmonary artery wedge pressure, and pulmonary artery pressure at restor during exercise should also be considered.

Indications for Mitral Valve ReplacementMitral valve replacement (MVR) is an accepted surgicalprocedure for patients with severe MS who are notcandidates for surgical commissurotomy or percutaneousmitral valvotomy. The risk of MVR is dependent onmultiple factors, including functional status, age, LVfunction, cardiac output, concomitant medical problems,and concomitant CAD. In the young, healthy person, MVRcan be performed with a risk of,5%. However, in theolder patient with concomitant medical problems or pul-monary hypertension at systemic levels, the risk of MVRmay be 10% to 20%.

If there is significant calcification, fibrosis, and subval-vular fusion of the mitral valve apparatus, commissurot-omy or percutaneous balloon valvotomy is less likely to besuccessful, and MVR will be necessary. Given the risk ofMVR and the potential long-term complications of aprosthetic valve, there are stricter indications for mitralvalve operation in these patients with calcified fibroticvalves. For the patient with NYHA functional Class IIIsymptoms due to severe MS or combined MS/MR, MVRresults in excellent symptomatic improvement. Postpone-




ment of surgery until the patient reaches the functionalClass IV symptomatic state should be avoided becauseoperative mortality is high and long-term outcome subop-timal. However, if the patient presents in NYHA functionalClass IV heart failure, surgery should not be deniedbecause the outlook without surgical intervention is grave.It is controversial whether asymptomatic or mildly symp-tomatic patients with severe MS (valve area,1 cm2) andsevere pulmonary hypertension (pulmonary artery systolicpressure.60 to 80 mm Hg) should undergo MVR toprevent right ventricular failure, but surgery is generallyrecommended in such patients. It is recognized that pa-tients with such severe pulmonary hypertension are rarelyasymptomatic.

Recommendations for Mitral Valve Replacement forMitral Stenosis

Indication Class

1. Patients with moderate or severe MS (mitral valve area<1.5 cm2)* and NYHA functional Class III-IV symptomswho are not considered candidates for percutaneousballoon valvotomy or mitral valve repair.

I

2. Patients with severe MS (mitral valve area <1 cm2)* andsevere pulmonary hypertension (pulmonary arterysystolic pressure >60 to 80 mm Hg) with NYHAfunctional Class I-II symptoms who are not consideredcandidates for percutaneous balloon valvotomy or mitralvalve repair.

IIa

*The committee recognizes that there may be a variability in themeasurement of mitral valve area and that the mean transmitral gradient,pulmonary artery wedge pressure, and pulmonary artery pressure shouldalso be considered.

Management of Patients After Valvotomyor CommissurotomyRecurrent symptoms after successful surgical commissurot-omy have been reported to occur in as many as 60% ofpatients after 9 years, but recurrent stenosis accounts forsymptoms in,20%. In patients with adequate initial results,progressive MR and development of other valvular or coro-nary problems are more frequently responsible for recurrentsymptoms. Thus, in patients presenting with symptoms lateafter commissurotomy, a comprehensive evaluation is re-quired to look for other causes of the symptoms. Patientsundergoing percutaneous mitral valvotomy have a higherincidence of recurrent symptoms at 1- to 2-year follow-up ifthere was an unfavorable mitral valve morphology due toeither an initial inadequate result or restenosis.

The management of patients after successful percutaneousballoon valvotomy or surgical commissurotomy is similar tothat of the asymptomatic patient with MS. A baseline echo-cardiogram should be performed after the procedure to assesshemodynamics as well as to exclude significant complica-tions such as MR, LV dysfunction, or atrial septal defect (inthe case of percutaneous valvotomy). The echocardiogramshould be performed$72 hours after the procedure becauseacute changes in atrial and ventricular compliance immedi-ately after the procedure affect the reliability of the half-timemethod in calculating valve area. Patients with severe MR ora large atrial septal defect should be considered for early

operation. However, the majority of small left-to-right shuntsat the atrial level will close spontaneously over the course of6 months. In patients with a history of atrial fibrillation,warfarin should be restarted 1 to 2 days after the procedure.

Repeat percutaneous balloon valvotomy can be performedin the patient who has restenosis after either a prior surgicalcommissurotomy or balloon valvotomy. The results of theseprocedures are less satisfactory than the overall results ofinitial valvotomy because there is usually more valve defor-mity, calcification, and fibrosis than with the initial proce-dure. MVR should be considered in those patients withrecurrent severe symptoms and severe deformity of the mitralapparatus.

D. Mitral Valve ProlapseMVP is the most common form of valvular heart disease andoccurs in 2% to 6% of the population. MVP often occurs asa clinical entity with little or no MR but is also the mostcommon cause of significant MR in the United States.

Primary and secondary MVP must be distinguished fromnormal variants by cardiac auscultation and/or echocardiogra-phy; these variations can result in an incorrect diagnosis ofMVP, particularly in patients with hyperkinetic hearts or dehy-dration. Other auscultatory findings may be misinterpreted asmidsystolic clicks or late systolic murmurs. Patients with mild tomoderate billowing of 1 or more nonthickened leaflets towardthe left atrium with the leaflet coaptation point on the LV side ofthe mitral annulus and minimal or no MR by Doppler echocar-diography are probably normal. Unfortunately, many such pa-tients are overdiagnosed as having the MVP syndrome.

Natural HistoryIn most patient studies, the MVP syndrome is associated witha benign prognosis. The age-adjusted survival rate of bothmen and women with MVP is similar to that of individualswithout this common clinical entity. The gradual progressionof MR in patients with MVP may result in progressivedilatation of the left atrium and ventricle. Left atrial dilatationmay result in atrial fibrillation, and moderate to severe MRmay eventually result in LV dysfunction and development ofcongestive heart failure. Pulmonary hypertension may occurwith associated right ventricular dysfunction. In some pa-tients, after an initially prolonged asymptomatic interval, theentire process may enter an accelerated phase as a result ofleft atrial and LV dysfunction, atrial fibrillation, and incertain instances, ruptured mitral valve chordae.

Several long-term prognostic studies suggest that compli-cations occur most commonly in patients with a mitralsystolic murmur, thickened redundant mitral valve leaflets,and increased LV or left atrial size, especially in men.45years of age. Sudden death is a rare complication of MVP,occurring in,2% of known cases during long-term follow-up, with annual mortality rates,1% per year.

Infective endocarditis is a serious complication of MVP,which is the leading predisposing cardiovascular diagnosis inmost series of patients reported with endocarditis. Becausethe absolute incidence of endocarditis is extremely low forthe entire MVP population, there has been much controversyabout the risk of endocarditis in MVP.




Evaluation and Management of the Asymptomatic PatientThe primary diagnostic evaluation of the patient with MVP isa carefulphysical examination.The principal cardiac auscul-tatory feature of this syndrome is the midsystolic click, whichmay vary considerably in intensity and timing according toLV loading conditions and contractility. Clicks result fromsudden tensing of the mitral valve apparatus as the leafletsprolapse into the left atrium during systole. The midsystolicclick(s) is frequently followed by a late systolic murmur,usually medium- to high-pitched and loudest at the cardiacapex. Dynamic auscultation is often useful for establishingthe clinical diagnosis of the MVP syndrome. Changes in LVend-diastolic volume result in changes in the timing of themidsystolic click(s) and murmur. When end-diastolic volumeis decreased (as with standing), the critical volume isachieved earlier in systole, and the click-murmur complexoccurs shortly after the first heart sound. By contrast, anymaneuver that augments the volume of blood in the ventricle(eg, squatting), reduces myocardial contractility, or increasesLV afterload, lengthens the time from onset of systole toinitiation of MVP, and the systolic click and/or murmur movetoward the second heart sound.

2-D and Doppler echocardiographyis the most useful non-invasive test for defining MVP. The M-mode echocardiographicdefinition of MVP includes$2-mm posterior displacement of 1or both leaflets or holosystolic posterior “hammocking”.3 mm.On 2-D echocardiography, systolic displacement of 1 or bothmitral leaflets in the parasternal long-axis view, particularlywhen they coapt on the atrial side of the annular plane, indicatesa high likelihood of MVP. There is disagreement about thereliability of echocardiographic diagnosis of MVP when ob-served in only the apical 4-chamber view. The diagnosis ofMVP is even more certain when leaflet thickness is.5 mm.Leaflet redundancy is often associated with an enlarged mitralannulus and elongated chordae tendineae. On Doppler echocar-diography, the presence or absence of MR is an importantconsideration, and MVP is more likely when MR is detected asa high-velocity eccentric jet in late systole.

At present, there is no consensus on the 2-D echocardio-graphic criteria for MVP. Because echocardiography is a tomo-graphic cross-sectional technique, no single view should beconsidered diagnostic. The parasternal long-axis view permitsvisualization of the medial aspect of the anterior mitral leafletand middle scallop of the posterior leaflet. If the findings ofprolapse are localized to the lateral scallop in the posteriorleaflet, they would be best visualized by the apical 4-chamberview. All available echocardiographic views should be used,with the provision that billowing of the anterior leaflet alone inthe 4-chamber apical view is not evidence of prolapse; however,displacement of the posterior leaflet or coaptation point in anyview, including the apical view, suggests the diagnosis ofprolapse. The echocardiographic criteria for MVP should in-clude structural changes, such as leaflet thickening, redundancy,annular dilatation, and chordal elongation.

Patients with echocardiographic evidence for MVP but noevidence of thickened/redundant leaflets or definite MR aremore difficult to classify. If such patients have clinicalauscultatory findings of MVP, the echocardiogram usuallyconfirms the diagnosis.

Recommendations for Echocardiography in Mitral Valve Prolapse*

Indication Class

1. Diagnosis, assessment of hemodynamic severity of MR,leaflet morphology, and ventricular compensation inpatients with physical signs of MVP.

I

2. To exclude MVP in patients who have been given thediagnosis when there is no clinical evidence to supportthe diagnosis.

I

3. To exclude MVP in patients with first-degree relativeswith known myxomatous valve disease.

IIa

4. Risk stratification in patients with physical signs of MVPor known MVP.

IIa

5. To exclude MVP in patients in the absence of physicalfindings suggestive of MVP or a positive family history.

III

6. Routine repetition of echocardiography in patients withMVP with mild or no regurgitation and no changes inclinical signs or symptoms.

III

*From the ACC/AHA Guidelines for the Clinical Application ofEchocardiography.2

Although there is controversy concerning the need forechocardiography in patients with classic auscultatory find-ings of MVP, the usefulness of echocardiography for riskstratification in patients with MVP has been demonstrated in$6 published studies. All patients with MVP should have aninitial echocardiogram. Serial echocardiograms are not usu-ally necessary in the asymptomatic patient with MVP unlessthere are clinical indications of severe or worsening MR.

Reassurance is a major part of themanagementof patientswith MVP, most of whom are asymptomatic or have nocardiac symptoms and lack a high-risk profile. These patientswith mild or no symptoms and findings of milder forms ofprolapse should be reassured of the benign prognosis. Anormal lifestyle and regular exercise are encouraged.

Antibiotic prophylaxis for prevention of infective endocarditisduring procedures associated with bacteremia is recommendedfor most patients with a definite diagnosis of MVP, as indicatedin section II.B. There has been some disagreement aboutwhether patients with an isolated systolic click and no systolicmurmur should undergo endocarditis prophylaxis. Patients withonly a systolic click who have echocardiographic evidence of ahigher-risk profile for endocarditis, such as leaflet thickening,elongated chordae, left atrial enlargement, or LV dilatation,should receive endocarditis prophylaxis.

Recommendations for Antibiotic Endocarditis Prophylaxis forPatients With Mitral Valve Prolapse Undergoing ProceduresAssociated With Bacteremia*

Indication Class

1. Patients with characteristic systolic click-murmur complex. I

2. Patients with isolated systolic click and echocardiographicevidence of MVP and MR.

I

3. Patients with isolated systolic click, echocardiographicevidence of high-risk MVP.

IIa

4. Patients with isolated systolic click and equivocal or noevidence of MVP.

III

*These procedures are defined in the American Heart Associationguidelines for prevention of endocarditis5 and in the full-text version ofthese guidelines.




Evaluation and Management of the Symptomatic PatientPatients with MVP and palpitations associated with mildtachyarrhythmias or increased adrenergic symptoms andthose with chest pain, anxiety, or fatigue often respond totherapy withb-blockers. However, in many cases, the cessa-tion of stimulants such as caffeine, alcohol, and cigarettesmay be sufficient to control symptoms. In patients withrecurrent palpitations, continuous or event-activated ambula-tory ECG recordings may reveal whether arrhythmias are thecause of symptoms and indicate appropriate treatment ofexisting arrhythmias. The indications for electrophysiologicaltesting are similar to those in the general population (eg,aborted sudden death, recurrent syncope of unknown cause,and symptomatic or sustained ventricular tachycardia).

Cardiac catheterization is not required for the diagnosis ofMVP. It is helpful in evaluating associated conditions (eg,CAD and atrial septal defect) and may be needed to assess thehemodynamic effects of severe MR (as well as coronaryartery anatomy) before consideration for valve repair orreplacement.

Daily aspirin therapy (80 to 325 mg/d) is recommended forpatients with MVP and documented focal neurological eventswho are in sinus rhythm with no atrial thrombi. Such patientsshould also avoid smoking cigarettes and using oral contra-ceptives. Long-term anticoagulation therapy with warfarin isrecommended for poststroke patients with MVP and patientswith MVP and recurrent transient ischemic attacks whilereceiving aspirin therapy (INR 2 to 3). Warfarin therapy isindicated in patients.65 years with MVP and atrial fibril-lation and those with MR, hypertension, or a history of heartfailure (INR 2 to 3). Aspirin therapy is satisfactory in patientswith atrial fibrillation who are,65, have no MR, and have nohistory of hypertension or heart failure. Daily aspirin therapyis also often recommended for patients with high-risk echo-cardiographic characteristics.

Recommendations for Aspirin and Oral Anticoagulants in MitralValve Prolapse

Indication Class

1. Aspirin therapy for cerebral transient ischemic attacks. I

2. Warfarin therapy for patients aged >65 years in atrialfibrillation with hypertension, MR murmur, or history ofheart failure.

I

3. Aspirin therapy for patients aged <65 years in atrialfibrillation with no history of MR, hypertension, or heartfailure.

I

4. Warfarin therapy for poststroke patients. I

5. Warfarin therapy for transient ischemic attacks despiteaspirin therapy.

IIa

6. Aspirin therapy for poststroke patients withcontraindications to anticoagulants.

IIa

7. Aspirin therapy for patients in sinus rhythm withechocardiographic evidence of high-risk MVP.

IIb

Asymptomatic patients with MVP and no significant MRcan be clinically evaluated every 3 to 5 years. Serial echo-cardiography is not necessary in most of these patients and isperformed only if there is development of symptoms consis-

tent with cardiovascular disease and a change in physicalfindings suggesting development of significant MR, and inpatients with high-risk characteristics observed on the initialechocardiogram. Patients with high-risk characteristics, in-cluding those with moderate to severe MR, should receive afollow-up once a year.

Patients with severe MR with symptoms and/or impairedLV systolic function require cardiac catheterization andevaluation for mitral valve surgery. The thickened, redundantmitral valve can often be repaired rather than replaced withlower operative mortality and excellent short- and long-termresults, as discussed in section III.E.

Surgical ConsiderationsManagement of MVP may require valve surgery, particularlyfor those who develop a flail mitral leaflet as a result ofrupture of chordae tendineae or their marked elongation.Most such valves can be successfully repaired by surgeonsexperienced in mitral valve repair, especially when theposterior leaflet of the mitral valve is predominantly affected.Symptoms of heart failure, severity of MR, the presence orabsence of atrial fibrillation, LV systolic function, LV end-diastolic and end-systolic volumes, and pulmonary arterypressure (at rest and during exercise) all influence thedecision to recommend mitral valve surgery. Recommenda-tions for surgery in patients with MVP and MR are the sameas those with other forms of nonischemic severe MR, asindicated in section III.E.4.

E. Mitral Regurgitation

1. Acute Severe Mitral RegurgitationIn acute severe MR, acute volume overload increases LVpreload, allowing for a modest increase in total LV strokevolume. However, forward stroke volume and cardiac outputare reduced, and the regurgitant volume results in pulmonarycongestion. In acute severe MR, the hemodynamic overloadoften cannot be tolerated, and mitral valve repair or replace-ment must often be performed urgently.

DiagnosisThe patient with acute severe MR is almost always symp-tomatic. Physical examination of the precordium may bemisleading because a normal-sized left ventricle does notproduce a hyperdynamic apical impulse. The systolic murmurof MR, which may or may not be holosystolic, and a thirdheart sound may be the only abnormal physical findingspresent. A fourth heart sound is common. Transthoracicechocardiography may demonstrate the disruption of themitral valve and help provide semiquantitative informationabout lesion severity. However, transthoracic echocardiogra-phy may underestimate lesion severity by inadequate imagingof the color flow jet. Because transesophageal echocardiog-raphy can more accurately assess the color flow jet, trans-esophageal imaging should be performed if mitral valvemorphology and regurgitant severity are still in question aftertransthoracic echocardiography. Transesophageal echocardi-ography is also helpful in demonstrating the anatomic causeof MR and directing successful surgical repair.

If ischemia is not the cause of MR and there is no reasonto suspect CAD, mitral valve repair can usually be performed




without cardiac catheterization. However, if CAD is sus-pected or there are risk factors for CAD, coronary arteriog-raphy is necessary before surgery.

Medical TherapyIn acute severe MR, the goal of nonsurgical therapy is todiminish the amount of MR, in turn increasing forward outputand reducing pulmonary congestion. In the normotensivepatient, administration of nitroprusside may effectively ac-complish all 3 goals. Nitroprusside alone should not beadministered to patients with hypotension, but combinationtherapy with an inotropic agent (such as dobutamine) andnitroprusside is of benefit in some patients. In such patients,aortic balloon counterpulsation increases forward output andmean arterial pressure while diminishing regurgitant volumeand LV filling pressure and can be used to stabilize hemo-dynamics while preparing for surgery. If infective endocar-ditis is the cause of acute MR, identification and treatment ofthe infectious organism are essential.

2. Chronic Mitral RegurgitationIn chronic severe MR, the increase in LV end-diastolicvolume permits an increase in total stroke volume, allowingfor restoration of forward cardiac output. Augmented preloadand reduced or normal afterload (provided by unloading ofthe left ventricle into the left atrium) facilitate LV ejection. Atthe same time, the increase in LV and left atrial size allowsaccommodation of the regurgitant volume at a lower fillingpressure. In this phase of compensated MR, the patient maybe entirely asymptomatic, even during vigorous exercise.

The duration of the compensated phase of MR varies but maylast for many years. However, the prolonged burden of volumeoverload may eventually result in LV dysfunction. In this phase,contractile dysfunction impairs ejection, and end-systolic vol-ume increases. There may be further LV dilatation and increasedLV filling pressure. These hemodynamic events result in re-duced forward output and pulmonary congestion. However, thestill favorable loading conditions often maintain ejection fractionin the low normal range (0.50 to 0.60) despite the presence ofsignificant muscle dysfunction. Correction of MR should occurbefore advanced LV decompensation.

DiagnosisIn evaluating the patient with chronic MR, a careful history isinvaluable. A well-established estimation of baseline exercisetolerance is important in gauging the subtle onset of symp-toms at subsequent evaluations. Physical examination shoulddemonstrate displacement of the LV apical impulse, whichindicates that MR is severe and chronic, producing cardiacenlargement. A third heart sound is usually present and doesnot necessarily indicate heart failure. An ECG and a chestx-ray are useful in establishing rhythm and heart size,respectively. An initial echocardiogram, including Dopplerinterrogation of the mitral valve, is indispensable in themanagement of MR. The echocardiogram provides a baselineestimation of LV and left atrial volume, an estimation of LVejection fraction, and approximation of the severity of regur-gitation. Changes from these baseline values are subsequentlyused to guide the timing of mitral valve surgery. In addition,the echocardiogram can often disclose the anatomic cause of

the patient’s condition. In the presence of even mild TR,interrogation of the tricuspid valve yields an estimate ofpulmonary artery pressure.

In some patients, Doppler studies show that MR worsenswith exercise, possibly reconciling exercise-induced symp-toms with resting echocardiograms that show only mild ormoderate regurgitation.

Serial TestingAsymptomatic patients with mild MR and no evidence of LVenlargement or dysfunction or pulmonary hypertension canbe followed up on a yearly basis with instructions to alert thephysician if symptoms develop in the interim. Yearly echo-cardiography is not necessary unless there is clinical evidencethat regurgitation has worsened. In patients with moderateMR, clinical evaluations should be performed annually, andechocardiography is not necessary more than once a year.

Asymptomatic patients with severe MR should be followedup with a history, physical examination, and echocardiogra-phy every 6 to 12 months to assess symptoms or transition toasymptomatic LV dysfunction. Serial chest x-rays and ECGsare of less value but are helpful in selected patients. Mostpatients develop symptoms before developing LV dysfunc-tion. Exercise stress testing may be used to add objectiveevidence of symptoms and changes in exercise tolerance.Exercise testing is especially important if a good history ofthe patient’s exercise capacity cannot be obtained.

Several studies have indicated that preoperative ejectionfraction is an important predictor of postoperative survival inpatients with chronic MR. The loading conditions of MRfacilitate ejection and increase ejection fraction, and theejection fraction in a patient with MR with normal LVfunction is usually $0.60. Consistent with this concept,postoperative survival is reduced in patients with a preoper-ative ejection fraction,0.60 compared with patients withhigher ejection fractions.

Alternatively or in concert, echocardiographic LV end-sys-tolic dimension (or volume) can be used in the timing ofmitral valve surgery. End-systolic dimension, which may beless load dependent than ejection fraction, should be,45 mmbefore surgery to ensure normal postoperative LV function. Ifpatients become symptomatic, they should undergo mitralvalve surgery even if LV function is normal.

Recommendations for Transthoracic Echocardiography inMitral Regurgitation

Indication Class

1. For baseline evaluation to quantify severity of MR and LVfunction in any patient suspected of having MR.

I

2. For delineation of mechanism of MR. I

3. For annual or semiannual surveillance of LV function(estimated by ejection fraction and end-systolic dimension)in asymptomatic severe MR.

I

4. To establish cardiac status after a change in symptoms. I

5. For evaluation after MVR or mitral valve repair to establishbaseline status.

I

6. Routine follow-up evaluation of mild MR with normal LVsize and systolic function.

III




Recommendations for Transesophageal Echocardiography inMitral Regurgitation

Indication Class

1. Intraoperative transesophageal echocardiography toestablish the anatomic basis for MR and to guide repair.

I

2. For evaluation of MR patients in whom transthoracicechocardiography provides nondiagnostic imagesregarding severity of MR, mechanism of MR, and/or statusof LV function.

I

3. In routine follow-up or surveillance of patients with nativevalve MR.

III

Medical TherapyFor the asymptomatic patient with chronic MR, there is nogenerally accepted medical therapy. Although intuitively theuse of vasodilators may appear to be logical for the samereasons that they are effective in acute MR and chronic AR,there are no large long-term studies to indicate that they arebeneficial. Furthermore, because MR with normal ejectionfraction is a disease in which afterload is not increased, drugsthat reduce afterload might produce a physiological state ofchronic low afterload for which there is very little experience.Thus, in the absence of systemic hypertension, there is noknown indication for the use of vasodilating drugs in asymp-tomatic patients with preserved LV function.

In patients with MR who develop symptoms but havepreserved LV function, surgery is the most appropriatetherapy. If atrial fibrillation develops, heart rate should becontrolled with digitalis, rate-lowering calcium channelblockers,b-blockers, or, rarely, amiodarone. Although therisk of embolism with the combination of MR and atrialfibrillation may be less than that of MS and atrial fibrillation,INR should be maintained between 2 and 3 in patients withMR who develop atrial fibrillation.

Indications for Cardiac CatheterizationCardiac catheterization, with or without exercise, is necessarywhen there is a discrepancy between clinical and noninvasivefindings. Catheterization is also performed when surgery iscontemplated and there is uncertainty about the severity of MRafter noninvasive testing or when there is a need to assess extentand severity of CAD before surgery. In patients with MR whohave risk factors for CAD (advanced age, hypercholesterolemia,hypertension, etc) or when there is suspicion that MR isischemic in etiology (either because of known myocardialinfarction or suspected ischemia), coronary angiography shouldbe performed before surgery. For cases in which no reasonablesuspicion of CAD exists, coronary angiography can be avoided.

Obviously, patients should not undergo valve surgery unlessthe valve lesion is severe. In cases of chronic MR, noninvasiveimaging should demonstrate anatomic disruption of the valve orits apparatus, and color flow Doppler should indicate severe MR.Although the standard semiquantitative approach to determiningseverity of MR from ventriculography has its own limitations,ventriculography does provide an additional method to assessLV dilatation and function and to gauge severity of MR.Exercise hemodynamics and quantitative angiography may pro-vide additional information that is helpful for decision making.During the catheterization procedure,a right-heart catheteriza-tion should be performedif severity of MR is uncertain.

Recommendations for Coronary Angiography inMitral Regurgitation

Indication Class

1. When mitral valve surgery is contemplated in patientswith angina or previous myocardial infarction.

I

2. When mitral valve surgery is contemplated in patientswith >1 risk factor for CAD (see section VIII.B.).

I

3. When ischemia is suspected as an etiologic factor in MR. I

4. To confirm noninvasive tests in patients not suspected ofhaving CAD.

IIb

5. When mitral valve surgery is contemplated in patientsaged <35 years and there is no clinical suspicion of CAD.

III

Recommendations for Left Ventriculography andHemodynamic Measurements in Mitral Regurgitation

Indication Class

1. When noninvasive tests are inconclusive regarding theseverity of MR, LV function, or the need for surgery.

I

2. When there is a discrepancy between clinical andnoninvasive findings regarding severity of MR.

I

3. In patients in whom valve surgery is not contemplated. III

Indications for SurgeryThree different mitral valve operations are used to correct MR:mitral valve repair, MVR with preservation of part or all of themitral apparatus, and MVR with removal of the mitral apparatus.In most cases, mitral valve repair is the operation of choice whenthe valve is suitable for repair and appropriate surgical skill andexpertise are available. This procedure preserves the patient’snative valve without a prosthesis, avoiding the risk of long-termanticoagulation (except in patients in atrial fibrillation) or pros-thetic valve failure late after surgery. In addition, preservation ofthe mitral apparatus leads to better postoperative LV functionand survival than in cases when the apparatus is removed.However, mitral valve repair is technically more demandingthan MVR, may require longer extracorporeal circulation time,and may occasionally fail.

The advantage of MVR with preservation of the chordalapparatus is that this operation ensures postoperative mitralvalve competence, preserves LV function, and enhancespostoperative survival compared with MVR, in which theapparatus is disrupted. Its disadvantage is the use of aprosthetic valve, with the risks of deterioration in biologicalvalves or the need for anticoagulation in mechanical valves.

MVR in which the mitral valve apparatus is destroyedshould almost never be performed. It should be reserved forthose circumstances in which the native valve and apparatusare so distorted by the preoperative pathology (eg, rheumaticdisease) that the mitral apparatus cannot be saved.

Many factors are useful in the preoperative prediction ofsuccess of mitral valve repair. This prediction is based on thesurgeon’s skill and experience in performing repair and onthe location and type of mitral valve disease that caused MR.Nonrheumatic posterior leaflet prolapse due to degenerativemitral valve disease or a ruptured chorda tendineae canusually be repaired. Involvement of the anterior leafletdiminishes the likelihood of repair, and consequently the skill




and experience of the surgeon are probably the most impor-tant determinants of whether the operation is eventuallyperformed. In general, rheumatic and ischemic involvementof the mitral valve and calcification of the mitral valveleaflets or annulus diminish the likelihood of repair even inexperienced hands.

1. Symptomatic Patients With Normal Left VentricularFunction.Patients with severe MR and symptoms of conges-tive heart failure despite normal LV function on echocardi-ography (ejection fraction.0.60 and end-systolic dimension,45 mm) require surgery. The feasibility of mitral valverepair is dependent on several factors, including valve anat-omy and surgical expertise. Successful surgical repair im-proves symptoms, preserves LV function, and avoids prob-lems associated with prosthetic valves. When repair is notfeasible, MVR with chordal preservation should relievesymptoms and maintain LV function.

2. Asymptomatic or Symptomatic Patients With Left Ven-tricular Dysfunction.The timing of surgery for asymptomaticpatients was once controversial, but most now agree thatmitral valve surgery is appropriate once the echocardiograph-ic indicators of LV dysfunction have appeared. These includeLV ejection fraction#0.60 and/or LV end-systolic dimension$45 mm. Although some would recommend a slightly lowerthreshold ejection fraction (0.55), it must be emphasized that,unlike timing of AVR for AR, LV ejection fraction should notbe allowed to fall into the low normal range in patients withchronic MR. The data regarding postoperative survival aremuch stronger with LV ejection fraction than end-systolicdimension, whereas both ejection fraction and end-systolicdimension strongly influence postoperative LV function andheart failure. Mitral valve surgery should also be recom-mended for symptomatic patients with evidence of LVsystolic dysfunction (ejection fraction#0.60, end-systolicdimension$45 mm). Determining the surgical candidacy ofthe symptomatic patient with MR and far-advanced LVdysfunction is a common clinical dilemma. If mitral valverepair appears likely, surgery should still be contemplated,provided ejection fraction is$0.30. Even though such apatient is likely to have persistent LV dysfunction, surgery islikely to improve symptoms and prevent further deteriorationof LV function.

3. Asymptomatic Patients With Normal Left VentricularFunction.Repair of a severely regurgitant valve may becontemplated in an asymptomatic patient with normal LVfunction to preserve LV size and function and prevent thesequelae of chronic MR. Although there are no data withwhich to recommend this approach to all patients, thecommittee recognizes that some experienced centers aremoving in this direction when there is a high likelihood ofsuccessful repair. This approach is often recommended inhemodynamically stable patients with newly acquired severeMR, as might occur with ruptured chordae. Surgery is alsorecommended in asymptomatic patients with chronic MRwith recent onset of episodic or chronic atrial fibrillation inwhom there is a high likelihood of successful valve repair(see below).

4. Atrial Fibrillation. Atrial fibrillation is a common, poten-tially morbid arrhythmia associated with MR. Preoperativeatrial fibrillation is an independent predictor of reducedlong-term survival after mitral valve surgery for chronic MR.The persistence of atrial fibrillation after mitral valve surgerypartially nullifies an advantage of mitral repair by requiringanticoagulation. Predictors of persistent atrial fibrillation aftersuccessful valve surgery are the presence of atrial fibrillationfor .1 year and left atrial size.50 mm. In 1 study, an evenshorter duration of preoperative atrial fibrillation (3 months)was a predictor of persistent atrial fibrillation after mitralvalve repair. Although patients who develop atrial fibrillationusually manifest other symptomatic or functional changesthat would warrant mitral valve repair or replacement, manyclinicians consider the onset of episodic or chronic atrialfibrillation to be an indication in and of itself for surgery.

Recommendations for Mitral Valve Surgery in NonischemicSevere Mitral Regurgitation

Indication Class

1. Acute symptomatic MR in which repair is likely. I

2. Patients with NYHA functional Class II, III, or IVsymptoms with normal LV function defined as ejectionfraction >0.60 and end-systolic dimension <45 mm.

I

3. Symptomatic or asymptomatic patients with mild LVdysfunction, ejection fraction 0.50 to 0.60, andend-systolic dimension 45 to 50 mm.

I

4. Symptomatic or asymptomatic patients with moderateLV dysfunction, ejection fraction 0.30 to 0.50, and/orend-systolic dimension 50 to 55 mm.

I

5. Asymptomatic patients with preserved LV function andatrial fibrillation.

IIa

6. Asymptomatic patients with preserved LV function andpulmonary hypertension (pulmonary artery systolicpressure >50 mm Hg at rest or >60 mm Hg withexercise).

IIa

7. Asymptomatic patients with ejection fraction 0.50 to0.60 and end-systolic dimension <45 mm andasymptomatic patients with ejection fraction >0.60and end-systolic dimension 45 to 55 mm.

IIa

8. Patients with severe LV dysfunction (ejection fraction<0.30 and/or end-systolic dimension >55 mm) inwhom chordal preservation is highly likely.

IIa

9. Asymptomatic patients with chronic MR with preservedLV function in whom mitral valve repair is highlylikely.

IIb

10. Patients with MVP and preserved LV function whohave recurrent ventricular arrhythmias despite medicaltherapy.

IIb

11. Asymptomatic patients with preserved LV function inwhom significant doubt about the feasibility of repairexists.

III

3. Ischemic Mitral RegurgitationThe outlook for the patient with ischemic MR is substantiallyworse than that for regurgitation from other causes, asischemic MR is usually caused by LV dysfunction and/orpapillary muscle dysfunction. On the other hand, coronaryartery bypass graft surgery may improve LV function andreduce ischemic MR, and in many patients with transient




severe MR due to ischemia, myocardial revascularization caneliminate episodes of severe MR.

Hypotension and pulmonary edema often occur in severeMR secondary to acute myocardial infarction. Treatment isaimed at hemodynamic stabilization, usually with insertion ofan intra-aortic balloon pump. Occasionally, revascularizationof the coronary artery supplying an ischemic papillary musclecan lead to improvement in mitral valve competence. How-ever, such improvement is rare, and correction of acute severeischemic MR usually requires valve surgery. Unlike nonis-chemic MR, in which mitral repair is clearly the operation ofchoice, the best operation for ischemic MR is controversial.

F. Multiple Valve DiseaseRemarkably few data exist to objectively guide managementof mixed valve disease. Each case must be consideredindividually and management based on understanding thepotential derangements in hemodynamics and LV functionand the probable benefit of medical versus surgical therapy.The committee has developed no specific recommendationsfor treatment of multiple valve disease. Specific valve lesionsare discussed in the full text of these guidelines.

G. Tricuspid Valve DiseaseTricuspid valve dysfunction can occur with normal or abnor-mal valves. Normal tricuspid valves develop regurgitationwith elevation of right ventricular systolic and/or diastolicpressure, right ventricular cavity enlargement, and tricuspidannular dilatation. Right ventricular systolic hypertensionoccurs in MS, pulmonic valve stenosis, and the variouscauses of pulmonary hypertension. Right ventricular diastolichypertension occurs in dilated cardiomyopathy and rightventricular failure of any cause.

DiagnosisThe physical examination is the initial key to diagnosis oftricuspid valve disease. Echocardiography is valuable inassessing valve structure and motion, measuring annular size,and identifying other cardiac abnormalities that might influ-ence tricuspid valve function. Doppler echocardiographyestimates severity of TR, right ventricular systolic pressure,and the tricuspid valve diastolic gradient. It should be pointedout that clinically insignificant TR is detected by colorDoppler imaging in many normal persons. This is not anindication for either routine follow-up or prophylaxis againstbacterial endocarditis. Thus, clinical correlation and judg-ment must accompany the echocardiographic results. Systolicpulmonary artery pressure estimation combined with infor-mation about annular circumference will further improve theaccuracy of clinical assessment.

ManagementIn patients with severe MS and pulmonary hypertension withresulting right ventricular dilatation and TR, relief of MS andthe resulting decrease in pulmonary artery pressure mayresult in substantial diminution of the degree of TR. Althoughthe timing of surgery for TR remains controversial, as do thesurgical techniques, this controversy has diminished since theadvent of 2-D and Doppler echocardiography for preopera-tive assessment. Intraoperative transesophageal Doppler

echocardiography allows refinement of annuloplasty tech-niques to optimize outcome.

Patients with severe TR of any cause have a poor long-termoutcome because of right ventricular dysfunction and/or sys-temic venous congestion. Tricuspid valve and chordal recon-struction can be attempted in some cases of TR that are the resultof endocarditis and trauma. In recent years, annuloplasty hasbecome an established surgical approach to significant TR.

When the valve leaflets themselves are diseased, abnormal, ordestroyed, valve replacement with a low-profile mechanicalvalve or bioprosthesis is often necessary. A biological prosthesisis preferred because of the high rate of thromboembolic com-plications with mechanical prostheses in the tricuspid position.

Recommendations for Surgery for Tricuspid Regurgitation

Indication Class

1. Annuloplasty for severe TR and pulmonary hypertensionin patients with mitral valve disease requiring mitralvalve surgery.

I

2. Valve replacement for severe TR secondary todiseased/abnormal tricuspid valve leaflets notamenable to annuloplasty or repair.

IIa

3. Valve replacement or annuloplasty for severe TR withmean pulmonary artery pressure <60 mm Hg whensymptomatic.

IIa

4. Annuloplasty for mild TR in patients with pulmonaryhypertension secondary to mitral valve diseaserequiring mitral valve surgery.

IIb

5. Valve replacement or annuloplasty for TR withpulmonary artery systolic pressure <60 mm Hg in thepresence of a normal mitral valve, in asymptomaticpatients, or in symptomatic patients who have notreceived a trial of diuretic therapy.

III

H. Valvular Heart Disease Associated WithAnorectic DrugsIn the summer of 1997, the association between anorexigensand valvular heart disease was reported in 24 patientsreceiving the drug combination of fenfluramine and phenter-mine; unusual valve morphology and associated regurgitationwere identified in both left- and right-sided heart valves. Theechocardiographic and histopathologic findings were similarto those described in patients with carcinoid or ergotamine-induced valvular heart disease. All 24 patients were symp-tomatic and had heart murmurs; thus, the frequency ofvalvular pathology in asymptomatic patients receiving thecombination of fenfluramine-phentermine could not be deter-mined. The FDA has reported 5 echocardiographic preva-lence surveys in which 86 of 271 patients (32%) who receiveda combination of fenfluramine and phentermine for 6 to 24months had evidence of significant AR and/or MR, as did 6of 20 patients (30%) who received dexfenfluramine with orwithout phentermine.

In light of this information, fenfluramine and dexfenflura-mine have been withdrawn from the market. The risk ofvalvular heart disease associated with exposure to fenflura-mine or dexfenfluramine, alone or in combination withphentermine, has been addressed in recent peer-reviewedstudies in which the prevalence of AR and/or MR in patients




exposed to these drugs varied widely. It does appear that theprevalence of significant valvular regurgitation may be re-lated to the duration of exposure to the anorectic agents andthat patients exposed for only brief periods of time have lessrisk of developing valvular regurgitation.

In addition to the uncertainties regarding the prevalence ofvalvular disease in patients receiving combination or single-drug therapy, the natural history of the valve disease duringanorectic drug treatment and after drug withdrawal is un-known and awaits further clinical investigation. Thus, the riskof valvular heart disease relative to the benefit of weightreduction in patients with morbid obesity is unknown.

Considering these unknown variables, it is not possible toderive definitive diagnostic and treatment guidelines forpatients who have received these anorectic drugs. Hence,clinical judgment is important. The US Department of Healthand Human Services (DHHS), through the Centers for Dis-ease Control and Prevention and the National Institutes ofHealth, has published interim recommendations.8

The Committee on Management of Patients With ValvularHeart Disease recommends that all patients with a history ofuse of fenfluramine or dexfenfluramine undergo a carefulhistory and thorough cardiovascular physical examination.Physical examination should include auscultation with thepatient in the upright position at end expiration to detect ARand in the left lateral decubitus position to detect MR. 2-Dand Doppler echocardiography should be performed in thosepatients with symptoms, cardiac murmurs, or other signs ofcardiac involvement (eg, widened pulse pressure or regurgi-tantc or v waves in the jugular venous pulse). Patients whosebody habitus prevents adequate cardiac auscultation shouldalso undergo 2-D and Doppler echocardiography. For exam-ple, mild AR may be difficult to detect on auscultation in anobese patient. Patients with clinical and echocardiographicevidence of valvular heart disease should then undergotreatment and/or further testing according to the recommen-dations developed for the specific valve lesions addressedearlier in these guidelines. Modification of these recommen-dations may be necessary as more information on the naturalhistory of these specific valve lesions becomes available.

In light of the current evidence, echocardiographic screen-ing of all patients with a history of fenfluramine or dexfen-fluramine use, especially asymptomatic patients without mur-murs or associated findings, is not recommended. However,because of possible progression of subclinical valvular dis-ease, asymptomatic patients without murmurs should undergorepeat physical examinations in 6 to 8 months.

Recommendations for Patients Who Have UsedAnorectic Drugs*

Indication Class

1. Discontinuation of the anorectic drug(s). I

2. Cardiac physical examination. I

3. Echocardiography in patients with symptoms, heartmurmurs, or associated physical findings.

I

4. Doppler echocardiography in patients for whom cardiacauscultation cannot be performed adequately becauseof body habitus.

I

Indication Class

5. Repeat physical examination in 6 to 8 months for thosewithout murmurs.

IIa

6. Echocardiography in all patients before dentalprocedures in the absence of symptoms, heartmurmurs, or associated physical findings.

IIb

7. Echocardiography in all patients without heartmurmurs.

III

*Fenfluramine or dexfenfluramine or the combination of fenfluramine-phentermine or dexfenfluramine-phentermine.

IV. Evaluation and Management ofInfective Endocarditis

A. Antimicrobial TherapyAntimicrobial therapy in endocarditis is guided by identifi-cation of the causative organism. Eighty percent of endocar-ditis cases are due to streptococci and staphylococci. Themajority of native valve endocarditis is caused byStrepto-coccus viridans(50%) andStaphylococcus aureus(20%).With prosthetic valve endocarditis, a wide spectrum oforganisms can be responsible within the first year of opera-tion. However, in “early” prosthetic valve endocarditis, usu-ally defined as endocarditis during the first 2 months aftersurgery,Staphylococcus epidermidisis the frequent offendingorganism. Late-onset prosthetic valve endocarditis followsthe profile of native valve endocarditis.Enterococcus faecalisand Enterococcus faeciumaccount for 90% of enterococcalendocarditis, usually associated with malignancy or manipu-lation of the genitourinary or gastrointestinal tract. Gram-positive and gram-negative bacilli are relatively uncommoncauses of endocarditis. In recent years, the HACEK group oforganisms (Haemophilus, Actinobacillus, Cardiobacterium,Eikenella, and Kingella species) have become importantcauses of endocarditis. Fungi, especiallyCandida,are impor-tant causes of endocarditis in patients with prosthetic valves,compromised immune systems, and intravenous drug abuse.Recommended antimicrobial regimens for treatment of bac-terial endocarditis have been published by the AHA9 and arereproduced in the full-text version of these guidelines.

B. Culture-Negative EndocarditisCulture-negative endocarditis most frequently (62%) resultsfrom prior antibiotic treatment before blood cultures weredrawn. The other reasons for negative blood cultures are infec-tions caused byCandida; Aspergillus; or fastidious, slow-growing organisms and noninfective endocarditis, such asLibman-Sacks endocarditis in patients with systemic lupuserythematosus. The recommended regimen for culture-negativepresumed bacterial endocarditis is a 6-week course of intrave-nous vancomycin (15 mg/kg every 12 hours) plus intravenous orintramuscular gentamycin (1 mg/kg every 8 hours).

C. Endocarditis in HIV Seropositive PatientsEndocarditis in patients who are HIV seropositive usuallyoccurs as a complication of drug injections or long-termindwelling central catheters.S aureusis the most frequentpathogen. Endocarditis-related mortality in patients withAIDS exceeds that of HIV-positive patients without AIDS.




Thus, it is recommended that endocarditis in patients withAIDS be treated with maximum-duration antibiotic regimens.

D. Indications for Echocardiographyin EndocarditisEchocardiography is useful for detection and characterizationof the hemodynamic and pathological consequences of infec-tion. These consequences include valvular vegetations; val-vular regurgitation; ventricular dysfunction; and associatedlesions such as abscesses, shunts, and ruptured chordae. Theindications for transthoracic and transesophageal echocardi-ography are discussed in the ACC/AHA Guidelines for theClinical Application of Echocardiography.2 Transesophagealimaging is more sensitive for detecting vegetations thantransthoracic imaging. Echocardiography may be useful inthe case of culture-negative endocarditis or the diagnosis of apersistent bacteremia whose source remains unidentified afterappropriate evaluation.

Recommendations for Echocardiography in InfectiveEndocarditis: Native Valves

Indication Class

1. Detection and characterization of valvular lesions, theirhemodynamic severity, and/or ventricularcompensation.*

I

2. Detection of vegetations and characterization of lesionsin patients with congenital heart disease in whominfective endocarditis is suspected.

I

3. Detection of associated abnormalities (eg, abscesses,shunts).*

I

4. Reevaluation studies in complex endocarditis (eg,virulent organism, severe hemodynamic lesion, aorticvalve involvement, persistent fever or bacteremia,clinical change, or symptomatic deterioration).

I

5. Evaluation of patients with high clinical suspicion ofculture-negative endocarditis.*

I

6. Evaluation of bacteremia without a known source.* IIa

7. Risk stratification in established endocarditis.* IIa

8. Routine reevaluation in uncomplicated endocarditisduring antibiotic therapy.

IIb

9. Evaluation of fever and nonpathological murmurwithout evidence of bacteremia.

III

*Transesophageal echocardiography may provide incremental value inaddition to information obtained by transthoracic imaging.


Recommendations for Echocardiography in InfectiveEndocarditis: Prosthetic Valves

Indication Class

1. Detection and characterization of valvular lesions, theirhemodynamic severity, and/or ventricularcompensation.*

I

2. Detection of associated abnormalities (eg, abscesses,shunts, etc).*

I

3. Reevaluation in complex endocarditis (eg, virulentorganism, severe hemodynamic lesion, aortic valveinvolvement, persistent fever or bacteremia, clinicalchange, or symptomatic deterioration).

I

Indication Class

4. Evaluation of suspected endocarditis and negativecultures.*

I

5. Evaluation of bacteremia without a known source.* I

6. Evaluation of persistent fever without evidence ofbacteremia or new murmur.*

IIa

7. Routine reevaluation in uncomplicated endocarditisduring antibiotic therapy.*

IIb

8. Evaluation of transient fever without evidence ofbacteremia or new murmur.

III

*Transesophageal echocardiography may provide incremental value inaddition to that obtained by transthoracic imaging.


E. Indications for Surgery in Patients With ActiveInfective EndocarditisSurgery is indicated in patients with life-threatening conges-tive heart failure or cardiogenic shock due to surgicallytreatable valvular heart disease with or without establishedinfective endocarditis if the patient’s prospects for recoveryare reasonable, with satisfactory quality of life after theoperation. Surgery should not be delayed in the setting ofacute infective endocarditis when congestive heart failureintervenes. Surgery is not indicated if complications (severeembolic cerebral damage) or comorbid conditions make theprospect of recovery remote.

The indications for surgery for infective endocarditis inpatients with stable hemodynamics are less clear. Earlyconsultation with a cardiovascular surgeon is recom-mended as soon as the diagnosis of aortic or mitral valveendocarditis is made so that the surgical team is aware ofthe patient who may suddenly need surgery. Surgery isrecommended for patients with annular or aortic abscesses,infections resistant to antibiotic therapy, and fungalendocarditis.

When endocarditis develops in patients with prosthetic valveswho are receiving warfarin anticoagulation, warfarin should bediscontinued and replaced with heparin. This recommendation isless related to the possibility of hemorrhagic complications ofendocarditis than the possibility of urgent surgery. If surgery isrequired, the effects of warfarin will have dissipated, and heparincan easily be reversed. Likewise, aspirin, if part of the medicalregimen, should also be discontinued. If neurological symptomsdevelop, anticoagulation should be discontinued until an intra-cranial hemorrhagic event is excluded by MRI or computedtomographic scanning.

Recommendations for Surgery for Native Valve Endocarditis*

Indication Class

1. Acute AR or MR with heart failure. I

2. Acute AR with tachycardia and early closure of themitral valve.

I

3. Fungal endocarditis. I

4. Evidence of annular or aortic abscess, sinus or aortictrue or false aneurysm.

I




Indication Class

5. Evidence of valve dysfunction and persistent infectionafter a prolonged period (7 to 10 days) of appropriateantibiotic therapy, as indicated by presence of fever,leukocytosis, and bacteremia, provided there are nononcardiac causes for infection.

I

6. Recurrent emboli after appropriate antibiotic therapy. IIa

7. Infection with gram-negative organisms or organismswith a poor response to antibiotics in patients withevidence of valve dysfunction.

IIa

8. Mobile vegetations >10 mm. IIb

9. Early infections of the mitral valve that can likely berepaired.

III

10. Persistent pyrexia and leukocytosis with negative bloodcultures.

III

*Criteria also apply to repaired mitral and aortic allograft or autograftvalves. Endocarditis defined by clinical criteria with or without laboratoryverification; there must be evidence that function of a cardiac valve isimpaired.

Recommendations for Surgery for ProstheticValve Endocarditis*

Indication Class

1. Early prosthetic valve endocarditis (first 2 months orless after surgery).

I

2. Heart failure with prosthetic valve dysfunction. I

3. Fungal endocarditis. I

4. Staphylococcal endocarditis not responding to antibiotictherapy.

I

5. Evidence of paravalvular leak, annular or aorticabscess, sinus or aortic true or false aneurysm, fistulaformation, or new-onset conduction disturbances.

I

6. Infection with gram-negative organisms or organismswith a poor response to antibiotics.

I

7. Persistent bacteremia after a prolonged course (7 to 10days) of appropriate antibiotic therapy withoutnoncardiac causes for bacteremia.

IIa

8. Recurrent peripheral embolus despite therapy. IIa

9. Vegetation of any size on or near the prosthesis. IIb

*Criteria exclude repaired mitral valves or aortic allograft or autograftvalves. Endocarditis is defined by clinical criteria with or withoutlaboratory verification.

V. Management of Valvular Diseasein Pregnancy

A. Physiological Changes of PregnancyThe evaluation and management of valvular heart disease inthe pregnant patient requires an understanding of the normalphysiological changes associated with gestation, labor, deliv-ery, and the early postpartum period. On average, there is a50% increase in circulating blood volume during pregnancy,which is accompanied by a commensurate increase in cardiacoutput that usually peaks between the midportion of thesecond and third trimesters. The augmented cardiac output iscaused by an increase in stroke volume, although there is alsoa smaller increase in heart rate, averaging 10 to 20 bpm.Because of the effects of uterine circulation and endogenoushormones, systemic vascular resistance falls with a dispro-

portionately greater lowering of diastolic blood pressure anda wide pulse pressure. Inferior vena caval obstruction from agravid uterus in the supine position can result in an abruptdecrease in cardiac preload, leading to hypotension withweakness and lightheadedness. These symptoms resolvequickly with a change in position.

There is a further abrupt increase in cardiac output duringlabor and delivery related in part to the associated anxiety andpain. Uterine contractions can lead to marked increases inboth systolic and diastolic blood pressure. After delivery,there is an initial surge in preload related to the autotransfu-sion of uterine blood into the systemic circulation and tocaval decompression.

Pregnancy is also associated with a hypercoagulable state,owing to relative decreases in protein S activity, stasis, andvenous hypertension. Estrogens may interfere with collagendeposition within the media of the medium- and large-sizedmuscular arteries. Circulating elastase can break up the elasticlamellae and weaken the aortic media during pregnancy.Weakening of the vascular wall may in turn predispose todissection with or without an underlying connective tissuedisorder.

The increased blood volume and enhanced cardiac outputassociated with normal pregnancy can accentuate the mur-murs associated with stenotic heart valve lesions (eg, MS,AS). On the other hand, murmurs of AR or MR may actuallyattenuate in the face of lowered systemic vascular resistance.

B. EchocardiographyNormal pregnancy is accompanied by echocardiographicevidence of mild ventricular chamber enlargement. Pulmonicand tricuspid valvular regurgitation, as assessed by Dopplerinterrogation, is the rule rather than the exception. A largeminority of women will demonstrate Doppler evidence of“physiological” MR in the absence of structural valve dis-ease. Atrioventricular valve incompetence may be derivedfrom the annular dilatation that accompanies ventricularenlargement. Appreciation of these echocardiographic andDoppler findings in normal individuals is an importantfoundation for noninvasive evaluation of subjects with sus-pected valvular disease. The use of ultrasound during preg-nancy poses no risk to the mother or fetus.

C. General Management GuidelinesClinical experience has shown several cardiac conditions inwhich the physiological changes of pregnancy are poorlytolerated. Most experts would agree that pregnancy should bediscouraged for some conditions, such as cyanotic heartdisease, Eisenmenger syndrome, or severe pulmonary hyper-tension. Valvular heart lesions associated with increasedmaternal and fetal risk during pregnancy include severe ASwith or without symptoms, MR or AR with NYHA functionalClass III to IV symptoms, MS with NYHA functional ClassII to IV symptoms, valve disease resulting in severe pulmo-nary hypertension (pulmonary pressure.75% of systemicpressures), valve disease with severe LV dysfunction (EF,0.40), mechanical prosthetic valves requiring anticoagula-tion, and AR in Marfan syndrome.




Individual counseling usually requires a multidisciplinaryapproach and should include information about contracep-tion, maternal and fetal risks of pregnancy, and expectedlong-term outcomes. However, many patients with valvularheart disease can be successfully managed throughout preg-nancy and during labor and delivery with conservativemedical measures designed to optimize intravascular volumeand systemic loading conditions.

Simple interventions such as bed rest and avoidance of thesupine position should not be overlooked. Whenever possi-ble, symptomatic or severe valvular lesions should be ad-dressed and resolved before conception and pregnancy. Con-temporaneous management with a dedicated obstetrical teamaccustomed to working with high-risk patients is encouraged.

D. Specific Lesions

1. Mitral StenosisYoung pregnant women with a previous history of acuterheumatic fever and carditis should continue to receivepenicillin prophylaxis as indicated in the nonpregnant state.Patients with mild to moderate MS can almost always bemanaged with judicious use of diuretics andb-blockade. Caremust be taken to avoid vigorous volume depletion to protectagainst uretero-placental hypoperfusion.b-Blockers arechiefly indicated to treat or prevent tachycardia to optimizediastolic filling.

Patients with severe MS who are symptomatic beforeconception will not predictably tolerate the hemodynamicburden of pregnancy and should be considered for percuta-neous balloon mitral valvotomy before conception, providedthe valve is anatomically suitable. Patients with severe MSwho develop NYHA functional Class III-IV symptoms dur-ing pregnancy should undergo percutaneous balloonvalvotomy.

Rarely, medical management of patients with MS does notprevent repetitive or persistent heart failure during pregnancy.However, there is now a near 10-year experience with balloonmitral valvotomy, with either very limited fluoroscopy (,1 to2 minutes’ exposure with both pelvic and abdominal shield-ing) or echocardiographic guidance. The reported results withmitral balloon valvotomy have been excellent, with fewmaternal and/or fetal complications. Percutaneous mitralballoon valvotomy should be performed only in experiencedcenters and only after aggressive medical measures have beenexhausted. In developing countries, there is a long history ofsuccessful surgical closed commissurotomy for the pregnantwoman.

2. Mitral RegurgitationMVP is the most common cause of MR in pregnant women.The physical findings pertinent to MVP may be obscured orvaried by the physiological changes of pregnancy, especiallyincreased blood volume and reduced systemic vascular resis-tance. The associated MR can usually be managed medically,although on rare occasions, mitral valve surgery is requiredbecause of ruptured chordae and acute, severe worsening ofthe regurgitant lesion. When mitral valve surgery is required,repair is always preferred, as would be the case for any young

patient, but especially in relation to the desirability ofavoiding the potential need for anticoagulation.

3. Aortic StenosisThe most common cause of AS in pregnant women iscongenital bicuspid disease. Patients with mild to moderateobstruction and normal LV systolic function can usually bemanaged conservatively through the entire pregnancy. Pa-tients with more severe obstruction (pressure gradient.50 mm Hg) or symptoms should be advised to delayconception until relief of AS is obtained. There is anassociation between the presence of a bicuspid aortic valveand cystic medial necrosis, which may predispose to sponta-neous aortic dissection, usually in the third trimester.

4. Aortic RegurgitationIsolated AR, like MR, can usually be managed medicallywith a combination of diuretics and if necessary vasodilatortherapy. Women with symptoms and/or signs of LV failureshould be carefully monitored throughout labor and deliverywith strict attention to volume status and blood pressure. Aswith MR, surgery during pregnancy should be contemplatedonly for the control of refractory Class III or IV symptoms.Consideration of LV size or systolic function in less symp-tomatic patients should not apply.

5. Pulmonary Valve StenosisIsolated pulmonic stenosis is rarely a significant impedimentto a successful pregnancy. This lesion can be approached withpercutaneous valvotomy under echocardiographic guidancewhen necessary.

6. Marfan SyndromeSpontaneous aortic dissection and/or rupture are the mostfeared cardiovascular complications of Marfan syndromeassociated with pregnancy. Dissection can occur at anypoint along the aorta but most commonly originates in theascending portion. Enlargement of the aortic root.4.0 cmidentifies a particularly high-risk group, although a normaldimension is by no means a guarantee against this cata-strophic complication.

Any woman with Marfan syndrome who is contemplatingpregnancy should have a screening transthoracic echocardio-gram with careful assessment of aortic root dimensions.Enlargement$ 5.0 cm is considered an indication for electiverepair before conception, usually with a composite valve-graft conduit and reimplantation of the coronary arteries. Ifaortic root enlargement (.4.0 cm) is first detected duringpregnancy, some authorities recommend termination withprompt aortic repair, especially if serial echocardiographicstudies demonstrate progressive dilatation over time. Dissec-tion and rupture are most likely to occur during the thirdtrimester or near the time of delivery. Special care must betaken to provide adequate analgesia to prevent wide surges inblood pressure during labor and delivery. Obstetrical tech-niques to shorten the second stage of labor are appropriate.General anesthesia and cesarean section may allow moreoptimal hemodynamic control. The use of prophylacticb-blockade throughout pregnancy is strongly recommended.Finally, it should be pointed out that patients with Marfansyndrome and no identifiable cardiovascular abnormalities on




examination or echocardiographic study can be safely shep-herded through pregnancy and a normal vaginal delivery.

E. Endocarditis ProphylaxisThe Committee on Rheumatic Fever, Endocarditis, and Ka-wasaki Disease of the American Heart Association does notrecommend routine antibiotic prophylaxis in patients withvalvular heart disease undergoing uncomplicated vaginaldelivery or cesarean section unless infection is suspected.Antibiotics are optional for high-risk patients with prostheticheart valves, a previous history of endocarditis, complexcongenital heart disease, or a surgically constructed systemic-pulmonary conduit. Many practitioners routinely provideantibiotics.

F. Cardiac Valve SurgeryCardiac valve surgery is a difficult and complex undertakingin the pregnant patient. Even under ideal conditions, includ-ing the use of cardiopulmonary bypass techniques that pro-mote high flow rates and warm perfusion temperatures, thereis a high incidence of fetal distress, growth retardation, orwastage. If possible, it is always preferable to delay surgeryuntil the fetus is viable and a cesarean section can beperformed as part of a concomitant procedure. Surgery shouldbe pursued only in the setting of medically refractory symp-toms (pulmonary congestion), especially if a low outputsyndrome intervenes.

G. AnticoagulationPregnant patients with mechanical valve prostheses have anobligate need for anticoagulation. Unfortunately, significantproblems remain, along with an impressive risk to bothmother and fetus of either hemorrhage or thrombosis with theuse of either warfarin or heparin.

1. WarfarinWarfarin crosses the placenta and has been associated withan increased incidence of spontaneous abortion, fetaldeformity, prematurity, and stillbirth. The true incidenceof warfarin embryopathy has been difficult to ascertainfrom the reported case series and has ranged from,5% to67%; an estimate of 4% to 10% seems reasonable, basedon recent reports. The risk may be dose related and appearsto be highest if exposure occurs during the 6th to 12thweek of gestation. Fetal cerebral hemorrhage can compli-cate labor and delivery, especially if forceps evacuation isnecessary.

2. HeparinHeparin does not cross the placenta and is generallyconsidered safer. However, its longer-term use is compli-cated by sterile abscesses, osteoporosis (albeit with a smallrisk of fracture), thrombocytopenia, and bleeding. Numer-ous reports attest to an unacceptable incidence of throm-boembolic complications, including fatal valve thrombo-sis, in high-risk pregnant women managed withsubcutaneous heparin (12% to 24%). These studies haveseveral limitations, such as inclusion of a predominantpopulation of women with older-generation and more

thrombogenic prostheses, inadequate heparin dosing,and/or lack of meticulous monitoring strategies. Unfortu-nately, the efficacy of adjusted-dose subcutaneous heparinhas not been definitively established.

The choice of anticoagulant must be carefully consideredand should consider the mother’s preferences regarding thecompeting risks to her and the fetus. For many women, a 4%to 10% risk of warfarin embryopathy is unacceptable. Thesewomen may be unwilling to take warfarin at any time duringthe first trimester or throughout the entire pregnancy. How-ever, implicit in their choice of heparin is the acceptance ofincreased risk of maternal hemorrhage or prosthetic valvethrombosis. Certainly, a full discussion of these issues isindicated before conception.

Recommendations for Anticoagulation During Pregnancy:Weeks 1 Through 35 in Patients With MechanicalProsthetic Valves

Indication Class

1. The decision whether to use heparin during the firsttrimester or to continue oral anticoagulation throughoutpregnancy should be made after full discussion withthe patient and her partner; if she chooses to change toheparin for the first trimester, she should be madeaware that heparin is less safe for her, with a higherrisk of both thrombosis and bleeding, and that any riskto the mother also jeopardizes the baby.*

I

2. High-risk women (a history of thromboembolism or anolder-generation mechanical prosthesis in the mitralposition) who choose not to take warfarin during thefirst trimester should receive continuous unfractionatedheparin intravenously in a dose to prolong themidinterval (6 hours after dosing) aPTT to 2 to 3 timescontrol. Transition to warfarin can occur thereafter.

I

3. In patients receiving warfarin, INR should bemaintained between 2.0 and 3.0 with the lowestpossible dose of warfarin, and low-dose aspirin shouldbe added.

IIa

4. Women at low risk (no history of thromboembolism,newer low-profile prosthesis) may be managed withadjusted-dose subcutaneous heparin (17 500 to 20 000U BID) to prolong the midinterval (6 hours after dosing)aPTT to 2 to 3 times control.

IIb

*From the European Society of Cardiology Guidelines for Prevention ofThromboembolic Events in Valvular Heart Disease.

Recommendations for Anticoagulation During Pregnancy: Afterthe 36th Week in Patients With Mechanical Prosthetic Valves

Indication Class

1. Warfarin should be stopped no later than week 36 andheparin substituted in anticipation of labor.

IIa

2. If labor begins during treatment with warfarin, acesarean section should be performed.

IIa

3. In the absence of significant bleeding, heparin can beresumed 4 to 6 hours after delivery and warfarin begunorally.

IIa

Low-molecular-weight heparins offer several potential ad-vantages over unfractionated heparin, including greater bio-availability, ease of administration, lack of need for labora-




tory monitoring, and a lower incidence of thrombocytopeniaand osteoporosis. Low-molecular-weight heparins do notcross the placenta. Although they have been used to treat deepvenous thrombosis in pregnant patients, there are no data toguide their use in the management of patients with mechan-ical heart valves. Dipyridamole is not an acceptable alterna-tive to aspirin because of its harmful effects on the fetus.Neither warfarin nor heparin is contraindicated in postpartummothers who breast-feed.

VI. Management of Valvular Heart Disease inAdolescents and Young Adults

Many patients with congenital heart disease have somevalvular involvement. Frequently, it is part of a more com-plex congenital cardiac anomaly. The management of thesecomplex diseases with multiple valve involvement is beyondthe scope of these guidelines. Rather, this section concernsisolated valve involvement in which it is the primary ana-tomic abnormality in adolescents and young adults.

A. Aortic StenosisAdolescents and young adults with isolated aortic valvestenosis almost always have congenital fusion of one or morecommissures, resulting in a bicuspid or unicuspid valve.Although the prevalence of bicuspid and unicuspid valvesmay be as high as 2%, only 1 of 50 children born with theseabnormalities will actually have significant obstruction orregurgitation by adolescence.

The rate of progression of AS during childhood andadolescence differs from that in the adult with acquiredAS. One third of children manifest an increase in thetransaortic gradient over a 4- to 8-year period. However,patients .12 years of age show very small increases.Those with higher initial gradients have a greater likeli-hood of progression.

Over the course of 20 years, only 20% of those with initialpeak LV to peak aortic pressure gradients,25 mm Hgrequire any intervention. However, in those with an initialpeak gradient.50 mm Hg, arrhythmias, sudden death, andother morbid events (including endocarditis, congestive heartfailure, syncope, angina, myocardial infarction, stroke, andpacemaker insertion) occur at a rate of'1.2% per year.Based on the experience of 370 patients followed up for'8000 patient-years, the incidence of sudden death is'0.3%per year. The severity of obstruction in those who died cannotbe determined, and a higher-risk subgroup cannot beexcluded.

Recommendations for Diagnostic Evaluation of the Adolescentor Young Adult With Aortic Stenosis*

Indication Class

1. ECG.* I

2. Echo-Doppler study.* I

3. Graded exercise test.† IIa

4. Cardiac catheterization† for evaluation of gradient. IIa

5. Chest x-ray.* IIb

Indication Class

6. Coronary arteriography in the absence of historysuggestive of concomitant CAD.

III

*Yearly if echo-Doppler gradient >36 mm Hg (velocity >3 m/s). Every2 years if echo-Doppler gradient <36 mm Hg (peak velocity <3 m/s).

†If echo-Doppler gradient >36 mm Hg (velocity >3 m/s) and patientinterested in athletic participation or if clinical findings and echo-Dopplerare disparate.

Balloon valvotomy is an efficacious treatment option forchildren and adolescents with AS caused by fusion of commis-sures. Although balloon dilation has become standard in childrenand adolescents with AS, it is rarely recommended in olderadults because even short-term palliation is uncommon. Thereare insufficient published data to establish an age cutoff. Untilmore information becomes available, recommendations for bal-loon valvotomy should be limited to adolescents and youngadults in their early 20s, although some older young adultswithout heavily calcified valves may also benefit.

Because balloon valvotomy has resulted in good long-termpalliation with little morbidity and little or no short- orintermediate-term mortality in children, adolescents, andyoung adults in their early 20s, the indications for interven-tion are considerably more liberal than those in older adults,for whom intervention usually involves valve replacement.

Children and young adults with Doppler gradients$70 to80 mm Hg (peak velocity.4.2 m/s), those who develop LVrepolarization or ischemic changes on the ECG (T-wave inversionor ST depression) at rest or with exercise, and those with symptomsmay be considered for cardiac catheterization and possible balloondilation. The gradient should be confirmed hemodynamically be-fore proceeding with dilation, and it is reasonable to performvalvotomy in patients with catheterization gradients.60 mm Hg.Patients with less severe gradients (50 to 70 mm Hg by Dopplerechocardiography) who are interested in participating in vigorousathletics or those contemplating pregnancy are also commonlyreferred for balloon dilation. In most centers, balloon valvotomy hasreplaced surgical valvotomy, but the latter remains a reasonablealternative if skilled interventional cardiologists are not available.

Recommendations for Aortic Balloon Valvotomy in theAdolescent or Young Adult (<21) With Normal Cardiac Output*

Indication Class

1. Symptoms of angina, syncope and dyspnea on exertion,with catheterization peak gradient >50 mm Hg.†

I

2. Catheterization peak gradient >60 mm Hg. I

3. New-onset ischemic or repolarization changes on ECGat rest or with exercise (ST depression, T-waveinversion over left precordium) with a gradient>50 mm Hg.†

I

4. Catheterization peak gradient >50 mm Hg if patientwants to play competitive sports or desires to becomepregnant.

IIa

5. Catheterization gradient <50 mm Hg without symptomsor ECG changes.

III

*Adolescents and young adults almost invariably have normal orincreased cardiac output. If cardiac index <2 L/min per m2, lowergradients should be used.

†If gradient <50 mm Hg, other causes of symptoms should be explored.




When balloon aortic valvotomy is ineffective or significantAR is present, valve replacement may be necessary. Replace-ment of the aortic valve with a pulmonary autograft, in whicha pulmonary or aortic homograft replaces the native pulmo-nary valve, as first performed by Ross, has recently gainedacceptance at some centers. Preliminary results indicate lowsurgical risk, with the majority of autograft valves performingwell for $1 decade. This approach has the advantage of notrequiring anticoagulation, an important issue for active ado-lescents and younger adults, including women contemplatingpregnancy.

B. Aortic RegurgitationThe indications for surgery in adolescents and young adultswith a bicuspid aortic valve with isolated AR or mixed aorticvalve disease are at present similar to adults; ie, symptoms,LV dysfunction (ejection fraction,0.50), or greatly in-creased LV end-diastolic or end-systolic diameter, taking intoaccount variations in body size. If the durability of pulmonaryautograft and homograft valves in the right ventricular out-flow tract is substantiated in long-term studies, the indicationsfor autograft valve replacement are likely to become moreliberal.

Recommendations for Aortic Valve Surgery (Replacement WithMechanical Valve, Homograft, or Pulmonary Autograft) in theAdolescent or Young Adult With Chronic Aortic Regurgitation

Indication Class

1. Onset of symptoms. I

2. Asymptomatic patients with LV systolic dysfunction(ejection fraction <0.50) on serial studies 1 to 3months apart.

I

3. Asymptomatic patients with progressive LV enlargement(end-diastolic dimension >4 SD above normal).

I

4. Moderate AS (gradient >40 mm Hg) (peak-to-peakgradient at cardiac catheterization).

IIb

5. Onset of ischemic or repolarization abnormalities (STdepression, T-wave inversion) over left precordium atrest.

IIb

C. Mitral RegurgitationIsolated congenital MR is an extremely uncommon cardiaccondition. The most common cause of MR in children isatrioventricular septal defects. MR can be associated withMVP in adolescents or young adults. The pathophysiology,diagnosis, and medical therapy of MR in adolescents issimilar to that discussed for the adult (see section III.E.).When symptoms or deteriorating LV systolic functiondevelop, surgery should be performed. Under most circum-stances, it is possible to decrease regurgitation with amitral annuloplasty. Occasionally, MVR with a mechani-cal or biological valve is necessary. When valve repairrather than MVR is likely, surgery for severe MR maybe contemplated in the absence of heart failure or LVdysfunction.

Recommendations for Mitral Valve Surgery in the Adolescent orYoung Adult With Congenital Mitral Regurgitation WithSevere MR

Indication Class

1. NYHA functional Class III or IV symptoms. I

2. Asymptomatic patients with LV systolic dysfunction(ejection fraction <0.60).

I

3. NYHA functional Class II symptoms with preserved LVsystolic function if valve repair rather than replacementis likely.

IIa

4. Asymptomatic patients with preserved LV systolicfunction in whom valve replacement is highly likely.

IIb

D. Mitral StenosisIn developed countries, virtually all MS in adolescents andyoung adults is congenital in origin. In the developing areasof the world, MS is more likely to result from rheumaticfever. Congenital MS may be associated with a wide varietyof other congenital cardiac malformations of the left side ofthe heart, including coarctation of the aorta.

The clinical, ECG, and radiological features of congenital MSare similar to those of acquired MS in adults. The echocardio-gram is beneficial for evaluating the mitral valve apparatus andpapillary muscles and may provide considerable insight into thefeasibility of successful valve repair. The information obtainedfrom transthoracic imaging is usually sufficient, but in olderchildren, adolescents, and young adults, a transesophageal echo-cardiogram is sometimes necessary.

Recommendations for Mitral Valve Surgery in the Adolescent orYoung Adult With Congenital Mitral Stenosis

Indication Class

1. Symptomatic patients (NYHA functional Class III or IV)and mean mitral valve gradient >10 mm Hg on Dopplerechocardiography.

I

2. Mildly symptomatic patients (NYHA functional Class II)and mean mitral valve gradient >10 mm Hg on Dopplerechocardiographic study.

IIa

3. Systolic pulmonary artery pressure 50 to 60 mm Hgwith a mean mitral valve gradient >10 mm Hg.

IIa

4. New-onset atrial fibrillation or multiple systemic emboliwhile receiving adequate anticoagulation.

IIb

The surgical management of congenital MS has improvedconsiderably with the improved appreciation of the mecha-nism of mitral valve function and ability to visualize the valveafforded by transesophageal echocardiography. In those witha parachute mitral valve, creation of fenestrations among thefused chordae may increase effective orifice area and im-prove symptoms dramatically. MVR may occasionally benecessary but is especially problematic in those with ahypoplastic mitral annulus, who may require an annulus-enlarging operation. Balloon dilation of congenital MS wasrecently attempted, but its usefulness is unproved. This is oneof the most difficult and dangerous therapeutic catheteriza-tion procedures and should be undertaken only in centers withoperators who have established experience and skill in thisinterventional technique.




E. Tricuspid Valve DiseaseAcquired disease of the tricuspid valve is very uncommon inadolescents and young adults and is usually the result oftrauma, bacterial endocarditis in intravenous drug abusers,and small ventricular septal defects. Most cases of tricuspidvalve disease are congenital, with Ebstein’s anomaly of thetricuspid valve being the most common.

There is variation in the severity of the valve leafletabnormalities and TR. An interatrial communication, usuallyin the form of a patent foramen ovale, is present in mostpatients. If TR elevates right atrial pressure above left atrialpressure, right-to-left shunting can occur with resulting hy-poxemia. One or more accessory conduction pathways arequite common, with a risk of paroxysmal atrial tachycardia of'25%.

Patients with Ebstein’s anomaly may be asymptomaticwith no cyanosis and no atrial arrhythmias. More com-monly, they are cyanotic because of right-to-left shunting,which is associated with exercise intolerance. Right ven-tricular dysfunction may eventually lead to right-sidedcongestive heart failure frequently exacerbated by an atrialarrhythmia such as atrial tachycardia, atrial flutter, or atrialfibrillation.

Recommendations for Diagnostic Evaluation* of Ebstein’s Anomalyof the Tricuspid Valve in the Adolescent or Young Adult

Indication Class

1. ECG. I

2. Chest x-ray. I

3. Echo-Doppler study. I

4. Pulse oximetry at rest and/or during exercise. IIa

5. Electrophysiological study if documented or suspectedatrial arrhythmia.

IIa

*Initial evaluation and every 1 to 3 years, depending upon severity.

The natural history of Ebstein’s anomaly varies. Inpatients who present in the perinatal period, the 10-yearactuarial survival is 61%. In a study that included morechildren who presented after the perinatal period, theprobability of survival was 50% at 47 years of age.Predictors of poor outcome were NYHA functional ClassIII or IV symptoms, a cardiothoracic ratio.65%, or atrialfibrillation. However, patients with Ebstein’s anomalywho reach late adolescence and adulthood often have anexcellent outcome.

The surgical management of Ebstein’s anomaly remainschallenging. For older children, adolescents, and youngadults, tricuspid valve repair may be performed. Reconstruc-tion of the valve is possible occasionally, especially whenthere is a mobile anterior leaflet not tethered to the ventricularseptum.

Occasionally, the tricuspid valve is not reparable, andreplacement with a bioprosthesis or a mechanical valvemay be necessary. When present, atrial communicationsshould be closed. If an accessory pathway is present, itshould be mapped and obliterated either preoperativelyin the electrophysiology laboratory or at the time ofsurgery.

Recommendations for Surgery in the Adolescent or Young AdultWith Ebstein’s Anomaly With Severe Tricuspid Regurgitation

Indication Class

1. Congestive heart failure. I

2. Deteriorating exercise capacity (NYHA functional Class III or IV). I

3. Progressive cyanosis with arterial saturation <80% atrest or with exercise.

I

4. Progressive cardiac enlargement with cardiothoracic ratio>60%.

IIa

5. Systemic emboli despite adequate anticoagulation. IIa

6. NYHA functional Class II symptoms with valve probablyreparable.

IIa

7. Atrial fibrillation. IIa

8. Deteriorating exercise tolerance (NYHA functional Class II). IIa

9. Asymptomatic patients with increasing heart size. IIb

10. Asymptomatic patients with stable heart size. III

F. Pulmonic StenosisBecause the pulmonary valve is the least likely valve to beaffected by acquired heart disease, virtually all cases ofpulmonary valve stenosis or regurgitation are congenital inorigin. Most patients with stenosis have a conical or dome-shaped pulmonary valve formed by fusion of the valveleaflets, which project superiorly into the main pulmonaryartery. Occasionally, the valve may be thickened and dysplas-tic, with stenosis caused by the inability of the valve leafletsto move sufficiently during ventricular systole.

Symptoms are unusual in children or adolescents withpulmonary valve stenosis, even when severe. Adults withlong-standing severe obstruction may have dyspnea andfatigue secondary to an inability to increase cardiac outputadequately with exercise. Exertional syncope or light-headedness may occur, but sudden death is very unusual.Eventually, TR and right ventricular failure may occur.

At any age, if the foramen ovale is patent, right ventricularcompliance may be reduced sufficiently to elevate right atrialpressure, allowing right-to-left shunting and cyanosis. Thisincreases the risk of paradoxical emboli.

Recommendations for Initial Diagnostic Workup ofPulmonic Stenosis

Severity ofPulmonic Stenosis

IndicationMild*Class

Moderate-Severe†

Class

1. ECG. I I

2. Echo-Doppler study (transthoracic). I I

3. Chest x-ray. IIa IIa

4. Diagnostic cardiac catheterization. III IIb‡

*Right ventricular to pulmonary artery maximum instantaneous gradi-ent <30 mm Hg by Doppler echocardiography.

†Right ventricular to pulmonary artery gradient >30 mm Hg by Dopplerechocardiography.

‡If catheterization gradient >50 mm Hg, balloon valvuloplasty shouldbe performed (see recommendations for intervention).




Clinical CourseThe clinical course of children and young adults with pulmo-nary valve stenosis has been well described. The secondNatural History Study of Congenital Heart Defects, reportedin 1993, found that the probability of 25-year survival was96%. Less than 20% of patients initially managed medicallysubsequently required a valvotomy, and only 4% of operatedpatients required a second operation. For patients with aninitial transpulmonary gradient,25 mm Hg, 96% did notrequire surgery over a 25-year period.

Infective endocarditis is very uncommon, occurring withan incidence of 0.94 per 10 000 patient years.

Surgical relief of severe obstruction by valvotomy with atransventricular or transpulmonary artery approach predates theintroduction of cardiopulmonary bypass. Balloon valvotomy hasnow become the procedure of choice for the typically domed,thickened valve in both children and adults virtually everywherein the United States. Surgery is still required for the dysplasticvalve often seen in Noonan syndrome. Although long-termfollow-up of pulmonary balloon valvotomy is not yet available,early and midterm results (up to 10 years) suggest that the resultswill be similar to surgical valvotomy, ie, little or no recurrenceover a 22- to 30-year period.

Recommendations for Intervention in the Adolescent or YoungAdult With Pulmonic Stenosis (Balloon Valvotomy or Surgery)

Indication Class

1. Patients with exertional dyspnea, angina, syncope, orpresyncope.

I

2. Asymptomatic patients with normal cardiac output(estimated clinically or determined by catheterization).

a. Right ventricular to pulmonary artery peak gradient>50 mm Hg

I

b. Right ventricular to pulmonary artery peak gradient40 to 49 mm Hg

IIa

c. Right ventricular to pulmonary artery peak gradient30 to 39 mm Hg

IIb

d. Right ventricular to pulmonary artery peak gradient<30 mm Hg

III

In those with severe or long-standing valvular obstruction,infundibular hypertrophy may cause secondary obstruction whenthe pulmonary valve is successfully dilated. This frequently re-gresses over time without treatment. Some have advocated transientpharmacologicalb-blockade, but there is insufficient information todetermine whether this is effective or necessary.

Recommendations for Follow-up Exams in Pulmonic Stenosis

Indication

Severity of Pulmonic Stenosis

Mild*Class

Moderate-Severe†Class

1. ECG. I I

2. Echo Doppler. I I

3. Chest x-ray. IIb IIa

4. Catheterization (forevaluation of gradient).

III III

*<29 mm Hg gradient; testing every 5 to 10 years.†>30 mm Hg gradient; testing every 3 years (consideration should be

given to balloon or surgical valvuloplasty).

G. Pulmonary RegurgitationPulmonary valve regurgitation is an uncommon congenitallesion occasionally seen with what has been described asidiopathic dilation of the pulmonary artery. Mild pulmonaryregurgitation may be a normal finding on Dopplerechocardiography.

Pulmonary regurgitation is an almost unavoidable resultof either surgical or balloon valvuloplasty of valvularpulmonic stenosis or surgical repair of tetralogy of Fallot.Among patients who undergo surgical valvotomy, 87%have pulmonary regurgitation by Doppler echocardiogra-phy, although it is audible in only 58%. Pulmonaryregurgitation after successful repair of tetralogy of Fallotusually has no long-term clinical consequence. However, asmall group with long-standing pulmonary regurgitationhas developed right ventricular dilatation and systolicdysfunction, which can lead to inability to augment cardiacoutput with exercise and in some cases congestive heartfailure. This group has also had a significant incidence ofventricular arrhythmias associated with late sudden death.Pulmonary valve replacement, usually with a homograft,has been performed, but follow-up data are too preliminaryto develop recommendations at this time.

VII. Management of Patients With ProstheticHeart Valves

A. Antibiotic Prophylaxis

1. Infective EndocarditisAll patients with prosthetic valves need appropriate antibioticsfor prophylaxis against infective endocarditis (section II.B.).

2. Recurrence of Rheumatic CarditisPatients with rheumatic heart disease continue to need anti-biotics for prophylaxis against recurrence of rheumatic car-ditis (section II.B.).

B. Antithrombotic TherapyAll patients with mechanical valves require warfarin therapy.The risk of embolism is greater with a valve in the mitralposition (mechanical or biological) compared with a valve inthe aortic position. With either type of prosthesis or valvelocation, the risk of emboli is probably higher in the first fewdays and months after valve insertion, before the valve isfully endothelialized.

1. Mechanical ValvesFor mechanical prostheses in the aortic position, INR shouldbe maintained between 2.0 and 3.0 for bileaflet valves andMedtronic Hall valves and between 2.5 and 3.5 for other diskvalves and Starr-Edwards valves; for prostheses in the mitralposition, INR should be maintained between 2.5 and 3.5 for




all mechanical valves. There was a difference of opinionregarding the Starr-Edwards valve in the aortic position, witha minority opinion recommending maintaining INR between2.0 and 3.0. The recommendation for higher INR values inthe mitral position is based on the greater risk of thrombo-embolic complications with mechanical valves in the mitralposition and the greater risk of bleeding at higher INRs. Inpatients with aortic mechanical prostheses who are at higherrisk of thromboembolic complications (see below), INRshould be maintained at 2.5 to 3.5 and the addition of aspirinconsidered. Some valves are thought to be more thrombo-genic than others (particularly the tilting disk valves), and acase could be made for increasing INR to between 3 and 4.5;however, this is associated with a considerably increased riskof bleeding.

The addition of low-dose aspirin (80 to 100 mg/d) towarfarin therapy (INR 2.0 to 3.5) further decreases the risk ofthromboembolism and decreases mortality due to other car-diovascular diseases. A slight increase in risk of bleedingwith this combination should be kept in mind. The risk ofgastrointestinal irritation and hemorrhage with aspirin is dosedependent over the range of 100 to 1000 mg/d, and theantiplatelet effects are independent of dose over this range.There are no data in patients with prosthetic heart valves whoare taking warfarin and aspirin in doses of 100 to 325 mg/d.Doses of 500 to 1000 mg/d clearly increase risk of bleeding.The addition of aspirin (80 to 100 mg/d) to warfarin should bestrongly considered unless there is a contraindication to theuse of aspirin (ie, bleeding or aspirin intolerance). Thiscombination is particularly appropriate for patients who havehad an embolus while on warfarin therapy, those with knownvascular disease, and/or those known to be particularlysusceptible to hypercoagulability.

It is important to note that thromboembolic risk is in-creased early after insertion of the prosthetic valve. The useof heparin early after prosthetic valve replacement and beforewarfarin achieves therapeutic levels is controversial. In somepatients, achievement of therapeutic INR can be delayedseveral days postoperatively because of mitigatingcomplications.

2. Biological ValvesBecause of an increased risk of thromboemboli in the first3 months after implantation of a biological prostheticvalve, anticoagulation with warfarin is usually recom-mended, although in several centers, only aspirin is usedfor biological valves in the aortic position. Risk is partic-ularly high in the first few days after surgery, and heparinshould be started as soon as the risk of increased surgicalbleeding is reduced. After 3 months, the biological valvecan be treated like native valve disease, and warfarin canbe discontinued in over two thirds of patients with biolog-ical valves. In the remaining patients with associated riskfactors for thromboembolism, such as atrial fibrillation,previous thromboembolism, or a hypercoagulable condi-tion, lifelong warfarin therapy is indicated to achieve anINR of 2.0 to 3.0. Many would also recommend continuinganticoagulation in patients with severe LV dysfunction(ejection fraction,0.30).

Recommendations for Antithrombotic Therapy in Patients WithProsthetic Heart Valves

Indication Class

1. First 3 months after valve replacement: Warfarin, INR 2.5 to 3.5 I

2. >3 months after valve replacement:

A. Mechanical valve

AVR and no risk factor*

Bileaflet valve or Medtronic Hall valveWarfarin, INR 2 to 3

I

Other disk valves or Starr-Edwards valveWarfarin, INR 2.5 to 3.5

I

AVR plus risk factor* Warfarin, INR 2.5 to 3.5 I

MVR Warfarin, INR 2.5 to 3.5 I

B. Bioprosthesis

AVR plus no risk factor* Aspirin, 80–100 mg/d I

AVR plus risk factor* Warfarin, INR 2 to 3 I

MVR plus no risk factor* Aspirin, 80–100 mg/d I

MVR plus risk factor* Warfarin, INR 2.5 to 3.5 I

3. Addition of aspirin, 80 to 100 mg once daily if not on aspirin. IIa

4. Warfarin, INR 3.5 to 4.5 in high-risk patients when aspirincannot be used.

IIa

5. Warfarin, INR 2.0 to 3.0 in patients with Starr-Edwards AVRand no risk factor.

IIb

6. Mechanical valve, no warfarin therapy. III

7. Mechanical valve, aspirin therapy only. III

8. Bioprosthesis, no warfarin and no aspirin therapy. III

*Risk factors: Atrial fibrillation, LV dysfunction, previous thromboem-bolism, and hypercoagulable condition.

3. Embolic Events During AdequateAntithrombotic TherapyIn the patient who has a definite embolic episode(s) whilereceiving adequate antithrombotic therapy, antithrombotictherapy should be increased as follows:

● Warfarin, INR 2 to 3: warfarin dose increased to achieveINR of 2.5 to 3.5

● Warfarin, INR 2.5 to 3.5: warfarin dose may need to beincreased to achieve INR of 3.5 to 4.5

● Not on aspirin: aspirin 80 to 100 mg/d should be initiated● Warfarin plus aspirin 80 to 100 mg/d dose may also need

to be increased to 325 mg/d if the higher dose of warfarinis not achieving the desired clinical result

● Aspirin alone: aspirin dose may need to be increased to 325mg/d and/or warfarin added to achieve an INR of 2 to 3

4. Excessive AnticoagulationIn most patients with INR above the therapeutic range,excessive anticoagulation can be managed by withholdingwarfarin and following the level of anticoagulation with serialINR determinations. Excessive anticoagulation (INR.5)greatly increases the risk of hemorrhage. However, rapiddecreases in INR that lead to INR falling below the thera-peutic level increase the risk of thromboembolism. Patientswith prosthetic heart valves with INR in the range of 5 to 10who are not bleeding can be managed by withholdingwarfarin and administering 2.5 mg of vitamin K1 orally. INRshould be determined after 24 hours and subsequently as




needed. Warfarin therapy is restarted and dose appropriatelyadjusted to ensure that INR is in the therapeutic range. Inemergency situations, the use of fresh frozen plasma ispreferable to high-dose vitamin K1, especially if givenparenterally.

5. Antithrombotic Therapy in Patients RequiringNoncardiac Surgery/Dental CareThe risk of increased bleeding during a procedure performedon a patient receiving antithrombotic therapy has to beweighed against the increased risk of thromboembolismcaused by stopping the therapy. The risk of stopping warfarincan be estimated and is relatively slight if the drug is withheldfor only a few days. When warfarin therapy is reinstituted,there are theoretic concerns about a hypercoagulable statecaused by suppression of protein C and protein S before thedrug affects the thrombotic factors. Although these risks areonly hypothetical, individuals at very high risk should betreated with heparin therapy until INR returns to the desiredrange.

Admission to the hospital or a delay in discharge to giveheparin is usually unnecessary. Determining which patientsare at very high risk of thrombosis and require heparin untilwarfarin can be reinstated may be difficult, and clinicaljudgment is required. Heparin can usually be reserved forthose who have had a recent thrombosis or embolus (arbi-trarily within 1 year), those with demonstrated thromboticproblems when previously off therapy, those with the Bjork-Shiley valve, and those with$3 “risk factors.” Risk factorsare atrial fibrillation, previous thromboembolism, a hyperco-agulable condition, and mechanical prosthesis; many wouldalso include LV dysfunction (ejection fraction,0.30) as arisk factor. A lower threshold for recommending heparinshould be considered in patients with mechanical valves inthe mitral position, in whom a single risk factor would besufficient evidence of high risk. Low-molecular-weight hep-arin is attractive as it is even more easily used outside thehospital; however, there are no data on patients with pros-thetic heart valves, and low-molecular-weight heparins can-not be recommended at this time.

6. Antithrombotic Therapy in Patients Needing CardiacCatheterization/AngiographyIn an emergent or semiemergent situation, cardiac catheter-ization can be performed with a patient taking warfarin butpreferably the drug should be stopped'72 hours before theprocedure so that INR is#1.5 (see above). The drug shouldbe restarted as soon as the procedure is completed. If a patienthas 1 or more risk factors that predispose to thromboembo-lism, heparin should be started when INR falls below 2.0 andcontinued when warfarin is restarted. After an overlap of 3 to5 days, heparin may be discontinued when the desired INR isachieved.

7. Thrombosis of Prosthetic Heart ValvesProsthetic valve obstruction may be caused by thrombusformation, pannus ingrowth, or a combination of these. If theprosthesis is obstructed by pannus, thrombolytic therapy willbe ineffective, and the valve needs to be replaced. Thrombo-lytic therapy for a prosthetic valve obstructed by thrombus is

associated with significant risks and is often ineffective.Thrombolytic therapy is ineffective in 16% to 18% ofpatients, and the rate of acute mortality is 6%. Risk ofthromboembolism is 12%; stroke, 3% to 10%; major bleedingepisodes, 5%; nondisabling bleeding, 14%; and recurrentthrombosis, 11%. Patients who have a large clot or evidenceof valve obstruction and who are in NYHA functionalClasses III or IV because of prosthetic thrombosis shouldundergo early/immediate reoperation. Thrombolytic therapyin such patients is reserved for those for whom surgicalintervention carries high risk and those with contraindicationsto surgery. Streptokinase and urokinase are the most fre-quently used thrombolytic agents. The duration ofthrombolytic therapy depends on resolution of pressure gra-dients and valve areas to near normal by Doppler echocardi-ography. Thrombolytic therapy should be stopped at 24 hoursif there is no hemodynamic improvement or after 72 hours,even if hemodynamic recovery is incomplete. If thrombolytictherapy is successful, it should be followed with intravenousheparin until warfarin achieves an INR of 3 to 4 for aorticprosthetic valves and 3.5 to 4.5 for mitral prosthetic valves. Ifpartially successful, thrombolytic therapy may be followed bya combination of subcutaneous heparin twice daily (toachieve aPTT of 55 to 80 seconds) plus warfarin (INR 2.5 to3.5) for a 3-month period.

Patients with a “small clot” who are in NYHA functionalClass I or II and those with LV dysfunction should havein-hospital, short-term intravenous heparin therapy. If this isunsuccessful, they may receive a trial of continuous infusionthrombolytic therapy over several days. If this is unsuccessfulor there is an increased risk associated with thrombolytictherapy, they may need reoperation. An alternative tothrombolytic therapy in patients who remain hemodynam-ically stable is to convert intravenous heparin to combinedtherapy with subcutaneous heparin (twice daily to an aPTT of55 to 80 seconds) and warfarin (INR 2.5 to 3.5) for 1 to 3months on an outpatient basis to allow endogenousthrombolysis. If intravenous heparin, heparin/thrombolytictherapy, or heparin/warfarin is successful, warfarin dosesshould be increased so that INR is between 3.0 and 4.0(around 3.5) for prosthetic aortic valves and 3.5 and 4.5(around 4.0) for prosthetic mitral valves. These patientsshould also receive low-dose aspirin.

C. Follow-up Visits

1. First Outpatient Postoperative VisitThe workup on this visit should include an interval orcomplete history and physical examination, ECG, chest x-ray,2-D and Doppler echocardiography, complete blood count,BUN/creatinine, electrolytes, lactase dehydroxygenase(LDH), and INR, if indicated. Echocardiography is the mostuseful noninvasive test. It provides information about pros-thesis stenosis/regurgitation, valve area, assessment of othervalve disease(s), pulmonary hypertension, atrial size, left andright ventricular hypertrophy, left and right ventricular sizeand function, and pericardial effusion/thickening. Echocardi-ography is an essential component of the first postoperativevisit because it assesses the effects and results of surgery and




serves as a baseline for comparison should complicationsand/or deterioration occur later.

2. Follow-up Visits in Patients Without ComplicationsPatients who have undergone valve replacement are not curedbut still have serious heart disease. They have exchangednative valve disease for prosthetic valve disease and must befollowed with the same care as patients with native valvulardisease.

The asymptomatic patient without complications needs tobe seen only at 1-year intervals. The frequency with which2-D and Doppler echocardiography should be performedroutinely in patients without complications is uncertain, andthere are no data on which to base this decision. Thecommittee did not reach consensus on this issue. The majorityrecommended no further echocardiographic testing after theinitial postoperative evaluation in patients with mechanicalvalves whose condition is stable and who have no symptomsor clinical evidence of LV dysfunction, prosthetic valvedysfunction, or dysfunction of other heart valves in keepingwith the ACC/AHA Guidelines for the Clinical Applicationof Echocardiography.2 The committee also failed to reachconsensus about serial echocardiography in patients withbioprosthetic valves, who have an increasing risk of structuraldeterioration of the valve after 5 years in the mitral positionand 8 years in the aortic position. A minority opinionrecommended annual echocardiography, whereas the major-ity recommended detailed histories and cardiac physicalexaminations with echocardiography when dictated by clini-cal circumstances, such as a regurgitant murmur or a changein symptoms. Once regurgitation is detected, close follow-upwith 2-D and Doppler echocardiography every 3 to 6 monthsis indicated. The committee agreed that echocardiography isindicated for any patient with a prosthetic heart valve when-ever there is evidence of a new murmur, there are questionsof prosthetic valve integrity and function, or there areconcerns about ventricular function.

Recommendations for Follow-up Strategy of Patients WithProsthetic Heart Valves

Indication Class

1. History, physical exam, ECG, chest x-ray,echocardiogram, complete blood count, serumchemistries, and INR (if indicated) at first postoperativeoutpatient evaluation.*

I

2. Radionuclide angiography or MRI to assess LV functionif result of echocardiography is unsatisfactory.

I

3. Routine follow-up visits at yearly intervals with earlierreevaluations for change in clinical status.

I

4. Routine serial echocardiograms at time of annualfollow-up visit in absence of change in clinical status.

IIb

5. Routine serial fluoroscopy. III

*This evaluation should be performed 3 to 4 weeks after hospitaldischarge. In some settings, the outpatient echocardiogram may bedifficult to obtain; if so, an inpatient echocardiogram may be obtainedbefore hospital discharge.

3. Follow-up Visits in Patients With ComplicationsLV dysfunction and clinical heart failure after valve replace-ment may be the result of (1) preoperative LV dysfunction

that persists or improves only partially; (2) perioperativemyocardial damage; (3) other valve disease that has pro-gressed; (4) complications of prosthetic heart valves; and (5)associated heart disease, such as CAD and systemichypertension.

Any patient with a prosthetic heart valve who does notimprove after surgery or who later shows deterioration offunctional capacity should undergo appropriate testing, in-cluding 2-D and Doppler echocardiography and, if necessary,transesophageal echocardiography and cardiac catheteriza-tion with angiography to determine the cause.

D. Major Criteria for Valve SelectionIn general, mitral valve repair is preferable to replacement,provided that it is feasible and the appropriate skill and experi-ence are available to perform the procedure successfully.

The major advantages of a mechanical valve are anextremely low rate of structural deterioration and a bettersurvival rate in patients,65 years old after AVR and forMVR in patients #50 years old after MVR. The majordisadvantages are increased incidence of bleeding due to theneed for antithrombotic therapy and cost and disadvantagesof antithrombotic therapy.

The major advantage of a bioprosthesis (whether porcineor pericardial) is lack of need for antithrombotic therapy. Inaddition, the rate of structural valve deterioration in the aorticposition in patients$65 years is lower than in patients,65,especially in the aortic position. In patients$65 yearsundergoing AVR with a porcine bioprosthesis, the rate ofstructural deterioration is,10% at 10 years. The majordisadvantage is the increased rate of structural valve deteri-oration and hence the need for reoperation in patients,65years, particularly in those#50 years. Pericardial biopros-theses may have a lower rate of structural valve deteriorationthan porcine bioprostheses in patients$65 years.

Pregnancy after valve replacement poses a difficultproblem. The disadvantages of a mechanical valve are thatthe patient is at risk for complications of warfarin therapythat may affect the patient and/or fetus and complicationsof heparin therapy (see section V.G.). The disadvantage ofa bioprosthesis is the relatively higher rate of earlystructural valve deterioration. The Ross procedure (pul-monary autograft) or an aortic valve homograft is associ-ated with a lower rate of such complications in youngwomen and does not require anticoagulation. These pro-cedures are strongly recommended for women who wish tobecome pregnant, provided that the necessary surgical skilland experience in performing these procedures areavailable.

If the patient needs antithrombotic therapy for any reason,for example, atrial fibrillation or presence of a mechanicalvalve in another position, the major advantage of a biologicalvalve is reduced substantially.

Biological valves have a much higher rate of structuraldeterioration when implanted in patients with renal failure,those on hemodialysis, and those with hypercalcemia. Ado-lescent patients who are still growing have a high risk foraccelerated biological valve calcification.




Recommendations for Valve Replacement With aMechanical Prosthesis

Indication Class

1. Patients with expected long life spans. I

2. Patients with a mechanical prosthetic valve already inplace in a different position than the valve to bereplaced.

I

3. Patients in renal failure, on hemodialysis, or withhypercalcemia.

II

4. Patients requiring warfarin therapy because of riskfactors* for thromboembolism.

IIa

5. Patients <65 years for AVR and <70 years for MVR.† IIa

6. Valve rereplacement for thrombosed biological valve. IIb

7. Patients who cannot or will not take warfarin therapy. III

*Risk factors: atrial fibrillation, severe LV dysfunction, previous throm-boembolism, and hypercoagulable condition.

†The age at which patients may be considered for bioprosthetic valvesis based on the major reduction in rate of structural valve deteriorationafter age 65 and the increased risk of bleeding in this age group.

Recommendations for Valve Replacement With a Bioprosthesis

Indication Class

1. Patients who cannot or will not take warfarin therapy. I

2. Patients >65 years* needing AVR who do not have riskfactors for thromboembolism.†

I

3. Patients considered to have possible complianceproblems with warfarin therapy.

IIa

4. Patients >70 years* needing MVR who do not have riskfactors for thromboembolism.†

IIa

5. Valve rereplacement for thrombosed mechanical valve. IIb

6. Patients <65 years.* IIb

7. Patients in renal failure, on hemodialysis, or withhypercalcemia.

III

8. Adolescent patients who are still growing. III

*The age at which patients should be considered for bioprostheticvalves is based on the major reduction in rate of structural valvedeterioration after age 65 and increased risk of bleeding in this agegroup.

†Risk factors: atrial fibrillation, severe LV dysfunction, previous throm-boembolism, and hypercoagulable condition.

VIII. Evaluation and Treatment of CoronaryArtery Disease in Patients With Valvular

Heart DiseaseMany patients with valvular heart disease have concomitantCAD, but the data are limited regarding optimal strategies fordiagnosis and treatment of CAD in such patients. Thus,management decisions are usually developed by blendinginformation from the randomized studies of treatment ofCAD and smaller published series of patients undergoingsurgical treatment of valvular heart disease.

A. Probability of Coronary Artery Disease inPatients With Valvular Heart DiseaseIschemic symptoms in patients with valvular heart diseasemay have multiple causes, such as LV chamber enlargement,increased wall stress or wall thickening with subendocardialischemia, and right ventricular hypertrophy. In general, be-

cause angina is a poor marker of CAD in patients with AS,coronary arteriography is recommended in symptomatic pa-tients before AVR, especially in men.35 years of age,premenopausal women.35 years of age with coronary riskfactors, and postmenopausal women.

CAD is less prevalent in patients with AR and those withMS than in those with AS. Nonetheless, in symptomaticpatients and/or those with LV dysfunction, preoperativecoronary angiography is recommended in men.35 yearsold, premenopausal women.35 years old with coronaryrisk factors, and postmenopausal women.

The relation between MR and CAD is unique in that CADis frequently the cause of this valve lesion. The managementof these patients is discussed in section III.E.

B. Diagnosis of Coronary Artery DiseaseThe resting ECG in patients with valvular heart diseasefrequently shows ST-segment changes due to LV hypertro-phy, LV dilatation, or bundle branch block, which reduce theaccuracy of the ECG at rest and during exercise for thediagnosis of concomitant CAD.

Similarly, resting or exercise-induced regional wallmotion abnormalities are nonspecific markers for CAD inpatients with underlying valvular heart disease who haveLV hypertrophy and/or chamber dilatation, as are myocar-dial perfusion abnormalities induced by exercise or phar-macological stress. Thus, there are few indications formyocardial perfusion imaging with thallium 201 or tech-netium 99m perfusion agents in patients with severevalvular disease, and coronary arteriography remains themost appropriate method for definitive diagnosis of CAD.Noninvasive imaging is useful when CAD is suspected inpatients with mild valve stenosis or regurgitation andnormal LV cavity size and wall thickness.

Recommendations for Coronary Angiography in Patients WithValvular Heart Disease

Indication Class

1. Before valve surgery (including infective endocarditis) ormitral balloon commissurotomy in patients with:

I

• Chest pain

• Other objective evidence of ischemia

• Decreased LV systolic function

• History of CAD

• Coronary risk factors* (including advanced age)†

2. Patients with apparently mild to moderate valvular heartdisease but with

I

• Progressive (Class II or greater) angina

• Objective evidence of ischemia

• Decreased LV systolic function

• Overt congestive heart failure

3. Patients undergoing catheterization to confirm theseverity of valve lesions before valve surgery withoutpreexisting evidence of CAD, multiple coronary riskfactors, or advanced age.†

IIb




Indication Class

4. Young patients† undergoing nonemergent valve surgerywhen no further hemodynamic assessment bycatheterization is deemed necessary and no coronary riskfactors, no history of CAD, and no evidence of ischemiaare present.

III

5. Asymptomatic patients with valvular heart disease whenvalve surgery or balloon commissurotomy is not beingconsidered.

III

6. Patients having emergency valve surgery for acute valveregurgitation, aortic root disease, or infective endocarditiswhen there are no coronary risk factors, angina,objective evidence of ischemia, evidence of coronaryembolization, LV systolic dysfunction, or age <35 years.

III

*Patients undergoing mitral balloon valvotomy need not undergocoronary angiography based only on coronary risk factors.

†The age at which coronary angiography should be performed beforevalve surgery is difficult to define. The committee recommends coronaryangiography in men >35 years of age, premenopausal women >35 yearsof age with coronary risk factors, and postmenopausal women.

C. Treatment of Coronary Artery Disease at theTime of Aortic Valve ReplacementAs noted previously,$33% of patients with AS undergoingAVR have concomitant CAD. More than 50% of patients.70 years old have CAD. Combined coronary artery bypasssurgery has had little or no adverse effect on operativemortality. Moreover, combined coronary bypass grafting andAVR reduces the rates of perioperative myocardial infarction,operative mortality, and late mortality and morbidity, com-pared with patients with significant CAD who do notundergo revascularization at the time of AVR. Incompleterevascularization is associated with greater postoperativesystolic dysfunction and reduced survival rates after surgerycompared with patients who receive complete revasculariza-tion. For $1 decade, improved myocardial preservationtechniques have been associated with reduced overall opera-tive mortality, and it has become standard practice to bypassall significant coronary artery stenoses when possible inpatients undergoing AVR. The committee recommends thisapproach.

D. Aortic Valve Replacement in PatientsUndergoing Coronary Artery Bypass SurgeryPatients undergoing coronary artery bypass surgery whohave severe AS should undergo AVR at the time ofrevascularization. Decision making is less clear in patientswith mild to moderate AS and CAD requiring coronarybypass surgery. Controversy persists regarding the indica-tions for “prophylactic” AVR at the time of coronarybypass surgery in such patients. This decision should bemade only after the severity of AS is carefully determinedby Doppler echocardiography and cardiac catheterization.

It is difficult to predict whether a given patient with CAD andmild AS is likely to develop significant AS after revasculariza-tion. As noted previously (section III.A.), the natural history ofmild AS is variable, with some patients manifesting a relativelyrapid progression of AS, with a decrease in valve area of up to

0.3 cm2 per year and an increase in pressure gradient of 15 to19 mm Hg per year; however, the majority may show little or nochange. The average rate of reduction in valve area is'0.12 cm2

per year, but the rate of change in an individual patient isdifficult to predict.

Although definitive data are not yet available, patients withintermediate aortic valve gradients (30 to 50 mm Hg meangradient at catheterization or 3 to 4 m/s transvalvular velocityby Doppler echocardiography) who are undergoing coronaryartery bypass surgery may warrant AVR at the time ofrevascularization, but this is controversial because there arelimited data to indicate the wisdom of this general policy.

Recommendations for Aortic Valve Replacement in PatientsUndergoing Coronary Artery Bypass Surgery

Indication Class

1. In patients undergoing CABG who have severe AS whomeet the criteria for valve replacement (section III.A.).

I

2. In patients undergoing CABG who have moderate AS(mean gradient 30 to 50 mm Hg or Doppler velocity 3to 4 m/s).

IIa

3. In patients undergoing CABG who have mild AS (meangradient <30 mm Hg or Doppler velocity <3 m/s).

IIb

References1. Ritchie JL, Bateman TM, Bonow RO, et al. Guidelines for clinical use of

cardiac radionuclide imaging: report of the American College of Cardi-ology/American Heart Association Task Force on Assessment of Diag-nostic and Therapeutic Cardiovascular Procedures (Committee on Radio-nuclide Imaging), developed in collaboration with the American Societyof Nuclear Cardiology.J Am Coll Cardiol. 1995;25:521–547.

2. Cheitlin MD, Alpert JS, Armstrong WF, et al. ACC/AHA guidelines forthe clinical application of echocardiography: a report of the AmericanCollege of Cardiology/American Heart Association Task Force onPractice Guidelines (Committee on Clinical Application of Echocardiog-raphy), developed in collaboration with the American Society of Echo-cardiography.Circulation. 1997;95:1686–1744.

3. Gibbons RJ, Beasley JW, Bricker JT, et al. ACC/AHA guidelines forexercise testing: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Com-mittee on Exercise Testing).J Am Coll Cardiol. 1997;30:260–311.

4. Scanlon PJ, Faxon DP, Audet AM, et al. ACC/AHA guidelines forcoronary angiography: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Com-mittee on Coronary Angiography).J Am Coll Cardiol.In press.

5. Dajani AS, Taubert KA, Wilson W, et al. Prevention of bacterial endo-carditis: recommendations by the American Heart Association.Circu-lation. 1997;96:358–366.

6. Dajani A, Taubert K, Ferrieri P, Peter G, Shulman S. Treatment of acutestreptococcal pharyngitis and prevention of rheumatic fever: a statementfor health professionals: Committee on Rheumatic Fever, Endocarditis,and Kawasaki Disease of the Council on Cardiovascular Disease in theYoung, the American Heart Association.Pediatrics. 1995;96:758–764.

7. Cheitlin MD, Douglas PS, Parmley WW. 26th Bethesda conference:recommendations for determining eligibility for competition in athleteswith cardiovascular abnormalities. Task Force 2: acquired valvular heartdisease.J Am Coll Cardiol. 1994;24:874–880.

8. From the Centers for Disease Control and Prevention. Cardiac valvu-lopathy associated with exposure to fenfluramine and dexfenfluramine:US Department of Health and Human Services interim public healthrecommendations, November 1997.JAMA. 1997;278:1729–1731.

9. Wilson WR, Karchmer AW, Dajani AS, et al. Antibiotic treatment ofadults with infective endocarditis due to streptococci, enterococci, staph-ylococci, and HACEK microorganisms: American Heart Association.JAMA. 1995;274:1706–1713.

KEY WORDS: AHA Medical/Scientific Statementsn valvesn regurgitationn stenosisn mitral valve




Committee MembersTask Force MembersO. Russell, Thomas J. Ryan and Sidney C. Smith, Jr

Cheitlin, Kim A. Eagle, Timothy J. Gardner, Arthur Garson, Jr, Raymond J. Gibbons, Richard T. O'Gara, Robert A. O'Rourke, Shahbudin H. Rahimtoola, James L. Ritchie, Melvin D.

Fedderly, Michael D. Freed, William H. Gaasch, Charles R. McKay, Rick A. Nishimura, Patrick Robert O. Bonow, Blase Carabello, Antonio C. de Leon, Jr, L. Henry Edmunds, Jr, Bradley J.

Heart Disease)Task Force on Practice Guidelines (Committee on Management of Patients With ValvularSummary A Report of the American College of Cardiology/American Heart Association

Guidelines for the Management of Patients With Valvular Heart Disease: Executive

Print ISSN: 0009-7322. Online ISSN: 1524-4539 Copyright © 1998 American Heart Association, Inc. All rights reserved.

is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231Circulation doi: 10.1161/01.CIR.98.18.1949

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