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Home , Angina, Aortic stenosis, Heart failure, Mitral valve prolapse, Valvular heart disease

COVER ARTICLE CARDIOVASCULAR UPDATE

Valvular Disease: Review and Update BENJAMIN SHIPTON, D.O., Mercer, Pennsylvania HANEY WAHBA, M.D., Mercy of Pittsburgh, Pittsburgh, Pennsylvania

People with are living longer, with less morbidity, than ever before. Advances in surgical techniques and a better understanding of timing for sur- gical intervention account for increased rates of survival. remains the for diagnosis and periodic assessment of patients with valvular heart disease. Generally, patients with stenotic valvular lesions can be monitored clin- ically until symptoms appear. In contrast, patients with regurgitant valvular lesions require careful echocardiographic monitoring for left ventricular function and may require surgery even if no symptoms are present. Aside from prophylaxis, very little medical is available for patients with valvular heart disease; surgery is the treatment for most symptomatic lesions or for lesions causing left ventricular dysfunction even in the absence of symptoms. (Am Fam Physician 2001;63:2201-8.)

amily physicians routinely en- extended latent period during which the counter patients with valvular patient is . The survival of heart disease. Although major patients with aortic is nearly advances in our understand- normal until the onset of symptoms, ing of this disease have been when survival rates decrease sharply. Fmade in the past two decades, only After the onset of symptoms, average recently has there been evidence-based survival is only two to three years.1,3,4 literature from which to draw conclu- Although the rate of progression of aor- sions about its diagnosis and manage- tic stenosis is variable and difficult to ment. The American College of Cardiol- predict,4 approximately 75 percent of ogy and American Heart Association patients with will be dead (ACC/AHA) Task Force recently pub- three years after the onset of symptoms if lished comprehensive practice guidelines the is not replaced. Some pa- to help clinicians manage this challenging tients with severe aortic stenosis remain disorder.1,2 Improved surgical techniques, asymptomatic, while others with moder- noninvasive techniques for surveillance ate stenosis have symptoms attributable of left ventricular function and guidelines to the condition. for the timing of surgery have likely com- The normal aortic valve area averages bined to contribute to improved survival 2.5 cm2, and there should normally be no and decreased morbidity in patients with gradient. A valve area of less than 0.8 cm2 chronic valvular heart disease.1,3 or a gradient of more than 50 mm Hg represents critical stenosis capable of This article is one in a Aortic Stenosis 1,3 series developed in causing symptoms or . collaboration with the Aortic stenosis is usually idiopathic American Heart Associ- and results in calcification and degenera- ation. Guest editor of tion of the aortic leaflets. Persons born The most common physical sign of the series is Sidney C. with a are predis- aortic stenosis is a systolic ejection mur- Smith, Jr., M.D., Chief Science Officer, Ameri- posed to develop aortic stenosis. The mur that radiates to the neck. In mild can Heart Association, classic symptoms of , exertional aortic stenosis, the murmur peaks early Dallas. and dyspnea generally follow an in , but as the severity of stenosis

JUNE 1, 2001 / VOLUME 63, NUMBER 11 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 2201 used to estimate left Surgical intervention is indicated in patients with moderately and .1,2 Patients with severe severe aortic stenosis and evidence of left ventricular aortic stenosis should undergo echocardiog- dysfunction. raphy annually. This frequent monitoring is more for evaluation of left ventricular func- tion than for estimation of valve area. In patients with mild to moderate aortic stenosis, increases, the murmur peaks progressively performance of echocardiography every two later in systole and may become softer as car- to five years is appropriate for monitoring.1 diac output decreases (Table 1). As the steno- sis worsens, the aortic component of the sec- MANAGEMENT ond heart sound may become diminished. Patients with signs of aortic stenosis on The timing and amplitude of the carotid physical examination should undergo testing, correlate with the severity of aortic including chest x-ray, electrocardiograph stenosis.5(p118) Later in the disease, the carotid (ECG) and echocardiograph.1 There is upstrokes become diminished and delayed1,2,5 presently no medical therapy for aortic steno- (parvus et tardus; Figure 1). sis. Aortic is the only effec- tive treatment that will relieve this mechani- ECHOCARDIOGRAPHY cal obstruction.3 The decision for surgery is Echocardiography with Doppler provides based on the presence of at least moderately an accurate assessment of aortic valve area severe aortic stenosis with symptoms or signs and transvalvular gradient and also can be of left ventricular dysfunction. The with surgery is excellent, even for elderly patients (in the absence of comorbid condi- tions). In fact, the age-adjusted survival rate in postoperative patients is similar to that of LV Aortic the general population.3 Cardiac catheteriza- regurgitation tion with is warranted in the jet appropriate age and risk groups before aortic valve replacement is undertaken.1 RV . testing is not recommended in patients with aortic stenosis, especially . those who are symptomatic. Asymptomatic . Aortic valve patients may undergo exercise stress testing . only under the careful supervision of an RA experienced physician and with close moni- toring of pressure levels and ECGs.1 LA Patients with severe aortic stenosis should limit vigorous physical activity. Patients with aortic stenosis are at moderate risk for devel- opment of and should receive endocarditis prophylaxis before selected procedures.6 FIGURE 1. Five-chamber view (including the ) showing moderate aortic regurgitation. The transducer is positioned at the top of the Mitral Stenosis image. Regurgitant blood moving toward the transducer appears red on Doppler imaging or as a mosaic pattern, indicating turbulence. (RV The decline in has = right , LV = left ventricle, RA = right , LA = left atrium) reduced the incidence of mitral stenosis, a

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sequelae of rheumatic heart disease primar- ily affecting women.3 Mitral stenosis has a PHYSICAL EXAMINATION progressive, lifelong course that is slow and An apical rumbling, diastolic murmur is stable in the early years, with rapid accelera- characteristic and will immediately follow an tion later in life. There is generally a latent opening snap, if present. The rumble is loud- period of 20 to 40 years between the occur- est in early but, in patients with mild rence of rheumatic fever and the onset of mitral stenosis or mitral stenosis with low car- symptoms.1 diac output, the murmur may be difficult to Increased left atrial pressure and de- hear (Table 1).1,3,5(p271) It can be accentuated by creased produce the symp- placing the patient in the left lateral decubitus toms of mitral stenosis. Elevated left atrial position and using the bell of the . pressure eventually causes pulmonary vaso- Brief exercise (such as walking in the hallway) constriction, pulmonary and may also accentuate the murmur. A loud first compromise of right ventricular function. heart sound is common. A right ventricular Many patients remain asymptomatic until lift, elevated neck , and are atrial develops or until preg- later signs of right ventricular overload with nancy occurs, when there is increased . demand on the heart. Symptoms are gener- ally those of left-sided : dyspnea ECHOCARDIOGRAPHY on exertion, and paroxysmal noc- Echocardiography is the study of choice for turnal dyspnea. Patients may also present diagnosing and assessing the severity of with and signs of right-sided mitral stenosis. It is also useful for obtaining heart failure. an accurate valve area, assessing right ventric-

TABLE 1 Physical Examination of Patients with Valvular Heart Disease

Findings Murmur S1 S2 Other findings Maneuvers

Aortic stenosis Mid to late systolic; Normal Single or Carotid upstrokes Murmur softer with may be soft or paradoxically diminished and

absent if severe split delayed; S3 or S4 may be present Mitral stenosis Diastolic rumble Loud Normal Opening snap may Murmur increased be present with brief exercise Aortic Blowing diastolic Soft Normal Wide , Murmur increased regurgitation , with handgrip or hyperdynamic squatting circulation

Mitral Holosystolic Soft Normal or S3 may be present; Murmur louder with regurgitation split carotid upstrokes Valsalva maneuver brisk Mitral valve Mid to late systolic Normal Normal Mid-systolic click Murmur increased with standing

Information from references 1, 3 and 5.

JUNE 1, 2001 / VOLUME 63, NUMBER 11 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 2203 mended for patients who have New York Mechanical intervention is indicated in patients with mitral Heart Association class II, III or IV, moderate valve stenosis and mild symptoms or evidence of pulmonary or severe mitral stenosis and favorable valve morphology. The valves must be pliable, non- hypertension. calcified and free of subvalvular distortion.1,3 Candidates for valvotomy must have no sig- nificant mitral regurgitation.1 ular function and determining suitability for Open commissurotomy, mitral valve recon- balloon mitral valvotomy. struction and im- prove survival and reduce symptoms.1,3 Mitral MANAGEMENT valve replacement is indicated in patients with In patients who are asymptomatic, an severe mitral stenosis who are not candidates annual history and physical examination, as for valvotomy or commissurotomy. well as a chest x-ray and ECG, are recom- mended. Apart from endocarditis prophy- Aortic Regurgitation laxis, no medical therapy is indicated.3,6 When Aortic regurgitation results from disease mild symptoms develop, may be affecting the aortic root or aortic leaflets, pre- helpful in reducing left atrial pressure and venting their normal closure. Common decreasing symptoms. If causes of aortic regurgitation include endo- develops, rate control is critical since tachy- , rheumatic fever, vascular cardia will further decrease left ventricular disease, and .3 Bicus- filling, reduce cardiac output and increase left pid aortic valves are also prone to regurgita- atrial pressure, leading to more symptoms.1,3 tion. In chronic aortic regurgitation, the The timing of surgery correlates with the volume is increased, which in turn clinical outcome. If symptoms are more than causes systolic hypertension, high pulse pres- mild or if there is evidence of pulmonary sure and increased . The afterload in hypertension, mechanical intervention is aortic regurgitation may be as high as that warranted and delaying intervention worsens occurring in aortic stenosis.1 prognosis.3 Patients may be asymptomatic until severe Unlike valvotomy for aortic stenosis, bal- left ventricular dysfunction has developed. loon valvotomy for mitral stenosis provides The initial signs of aortic regurgitation are excellent mechanical relief with long-term subtle and may include decreased functional benefit.3 Mitral balloon valvotomy is recom- capacity or . As the disease progresses, the typical presentation is that of left-sided heart failure: orthopnea, dyspnea and fatigue. Systolic dysfunction is initially reversible, The Authors with full recovery of left ventricular size and function after . Over BENJAMIN SHIPTON, D.O., is in private practice in Mercer, Pa. A graduate of the Philadelphia College of Osteopathic Medicine, Philadelphia, he completed a family time, however, progressive chamber enlarge- medicine residency at Mercy Hospital of Pittsburgh, Pittsburgh, Pa. ment with decreased contractility make HANEY WAHBA, M.D., is faculty member at the Mercy Hospital family practice resi- recovery of left ventricular function and dency program and a clinical assistant professor in the department of family medicine improved survival impossible, even with at Jefferson Medical College of Thomas Jefferson University, Philadelphia. Dr. Wahba surgery.1 received his medical degree from the Cairo University Faculty of Medicine, Cairo, Egypt, and completed a residency in family practice at Latrobe Area Hospital in Latrobe, Pa. PHYSICAL EXAMINATION Address correspondence to Haney Wahba, M.D., MFHC-East 3424 William Penn Hwy., Penn Center Building No. 2, Pittsburgh, PA 15235 (e-mail: [email protected]). A diastolic blowing murmur heard along Reprints are not available from the authors. the left sternal border is characteristic of aor-

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tic regurgitation. A diastolic rumble may also be heard over the apex. The peripheral signs of Patients with chronic aortic regurgitation should undergo hyperdynamic circulation indicate severe dis- surgical intervention before the ejection fraction falls below ease (Table 1).1,3,5(p271) Some of these include 55 percent. Quincke’s pulse (alternating blanching and erythema of the nailbed with gentle pressure applied) and Musset’s sign (head bobbing).3 Although the mainstay of surgical treat- ECHOCARDIOGRAPHY ment has been replacement of the aortic valve Echocardiography with Doppler ultra- with a or mechanical prosthesis, inter- sonography provides information about aor- est in autograft procedures and aortic valve tic valve morphology and aortic root size, and reconstruction is increasing.3 All patients a semiquantitative estimate of the severity of with aortic regurgitation should receive aortic regurgitation (Figure 2).It provides appropriate endocarditis prophylaxis for valuable information about left ventricular selected procedures.6 size and function. Asymptomatic patients with severe aortic regurgitation should Mitral Regurgitation undergo annual echocardiographic examina- Causes of chronic mitral regurgitation tion. Patients with milder forms of aortic include , degenerative regurgitation should have echocardiography valvular disease () and if any change in symptoms occurs.2 rheumatic fever.3 Chronic mitral regurgita- tion is a state of leading to MANAGEMENT the development of left ventricular Aortic regurgitation should be corrected if the symptoms are more than mild. Com- pelling evidence supports surgical correction before the onset of permanent left ventricular Regurgitated jet damage, even in asymptomatic patients.1,3 As in patients with mitral valve regurgitation, LV timing of surgical intervention correlates with a good outcome. In patients with chronic aortic regurgitation, surgery should . be performed before the ejection fraction falls RV below 55 percent or the end-systolic dimen- . sion exceeds 55 mm.1,3 The end-systolic dimension is another gauge of left ventricular Mitral valve function that helps determine contractility RA and is less dependent on than ejec- LA tion fraction. Afterload reduction with vasodilators has been shown to improve left ventricular per- formance and reduce aortic regurgitation. Therapy with (Procardia) in par- ticular has been shown to delay the need for FIGURE 2. Echocardiogram of a 73-year-old man with new-onset atrial fibrillation. Moderate mitral regurgitation is seen on this apical view. surgery by two to three years in patients with The color on Doppler imaging indicates movement of blood away from severe aortic regurgitation and normal left the transducer, located at the top of the image. (RV = right ventricle, ventricular function.3 LV = left ventricle, RA = right atrium, LA = left atrium)

JUNE 1, 2001 / VOLUME 63, NUMBER 11 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 2205 examination. There may be displacement of The ejection fraction in patients with mitral valve regurgita- the left ventricular impulse. A soft first heart tion should be above normal. sound and a widely split second heart sound may be present. An S3 indicates severe disease but does not necessarily indicate heart failure (Table 1).1,3,5(p271) hypertrophy. The left atrium also enlarges to accommodate the regurgitant volume. ECHOCARDIOGRAPHY This compensated phase of mitral regurgi- Echocardiography can be used to deter- tation varies in duration but may last many mine the etiology and morphology of mitral years.1 The prolonged state of volume over- regurgitation, which are important in deter- load may eventually to decompensated mining suitability for (Fig- mitral regurgitation. This phase is charac- ure 3). Although a variety of methods are terized by impaired left ventricular func- used to quantify mitral regurgitation, tion, decreased ejection fraction and pul- echocardiography provides only a semiquan- monary congestion. titative estimate of its severity.3 In patients with severe mitral regurgitation, annual or PHYSICAL EXAMINATION semiannual estimation of left ventricular A holosystolic murmur that may radiate to function (ejection fraction and end-systolic the axilla, the upper sternal borders or the dimension) is indicated, even in the absence subscapular region is apparent on physical of symptoms.

MANAGEMENT In patients with chronic mitral regurgita- tion, left ventricular damage can occur while Echocardiographic evaluation of murmurs the patient remains asymptomatic. Therefore, surgery is indicated if left ventricular dysfunc- tion has begun to develop, even in the absence of symptoms.1,3 Generally, the ejection frac- Pathologic murmur: Nonpathologic murmur Diastolic murmur (flow murmur) tion of patients with mitral regurgitation Grade III or louder should be above normal. If the ejection frac- Holosystolic murmur tion falls to below 60 percent, the prognosis Mid-systolic click(s) worsens. End-systolic dimension is another Atypical radiation of murmur helpful gauge in determining the need for surgery. An end-systolic dimension over 45 Echocardiography with mm is also consistent with a poor prognosis. Doppler imaging Yes Cardiovascular signs or symptoms? In summary, patients should be referred for surgery if symptoms are moderate to severe, if the ejection fraction is less than 60 No percent or if the end-systolic dimension approaches 45 mm, even in the absence of Observe symptoms1,3 (Figure 3). Properly timed surgery gives patients with mitral regurgita- tion a postoperative survival rate similar to FIGURE 3. Indications for echocardiography in the evaluation of that of the general population. No studies murmurs. have demonstrated successful use of medical Information from references 1, 2 and 5. therapy, other than as prophylaxis against

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endocarditis, in the treatment of chronic mitral regurgitation.1,3 Reassurance about the low incidence of serious complica- Because mitral valve repair has a lower rate tions associated with mitral valve prolapse is a significant of mortality associated with surgery and a component in the management of these patients. better late outcome than mitral valve replace- ment, repair should be performed whenever possible.1 The better outcome of repair is thought to be associated with the geometric preservation of the left ventricular and mitral PHYSICAL EXAMINATION valve apparatus. Mitral valve repair also elim- The mid-systolic click, often accompanied inates the need for anticoagulation therapy in by a late systolic murmur, is the auscultatory patients who are in sinus rhythm and pre- hallmark of mitral valve prolapse (Table 1). vents the chance of prosthetic valve failure. The click results from a sudden tensing of the Mitral valve repair, however, is more techni- mitral valve apparatus as the leaflets prolapse cally demanding than mitral valve replace- into the left atrium. When end-diastolic vol- ment, making the surgeon’s skill and experi- ume is decreased (as with standing), the click- ence in performing the repair a predictor of murmur complex occurs shortly after the first success.1 The success of mitral valve repair heart sound. Maneuvers that increase end- surgery also depends on the location and type diastolic volume (such as squatting) cause the of mitral valve disease that caused the mitral click-murmur complex to move toward the regurgitation. second heart sound.

Mitral Valve Prolapse ECHOCARDIOGRAPHY Mitral valve prolapse occurs when varying New echocardiographic criteria for the portions of one or both leaflets of the mitral diagnosis of mitral valve prolapse are based valve extend or protrude abnormally above on the three-dimensional shape of the valve the mitral annulus into the left atrium. with clinical correlation. The new criteria Although the prevalence of mitral valve have improved sensitivity and specificity for prolapse was once thought to be as high as diagnosis of mitral valve prolapse.7 All 15 percent in the general population, more patients with signs or symptoms of mitral recent studies using new echocardiographic valve prolapse should have an initial echocar- criteria for diagnosis have suggested a preva- diograph. Serial echocardiography is usually lence of approximately 2.4 percent.7 not necessary unless mitral regurgitation is Many symptoms have been attributed to present.1 mitral valve prolapse, including chest , dyspnea, and . Previous MANAGEMENT studies have linked mitral valve prolapse to Reassurance is a major component of the serious long-term complications such as management of patients with mitral valve atrial fibrillation, syncope, stroke and sudden prolapse. Patients should be reminded of the death. More recent research, however, reveals low incidence of serious complications asso- no increased risk of these complications ciated with mitral valve prolapse, and physi- when patients with mitral valve prolapse are cians should attempt to allay fears of serious compared with those who have no pro- underlying heart disease. Patients with mitral lapse.7,8 In addition, the age-adjusted survival valve prolapse and symptoms such as chest rate in patients with mitral valve prolapse is pain, palpitations or anxiety often respond to similar to that in patients without mitral treatment with beta-blocking . In valve prolapse.1 many cases, cessation of alcohol, tobacco and

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caffeine use may be sufficient to control REFERENCES 1 symptoms. 1. Bonow RO, Carabello B, de Leon AC, Edmunds LH, Use of prophylaxis against endocarditis has Fedderly BJ, Freed MD, et al. Guidelines for the been controversial in patients with mitral management of patients with valvular heart dis- ease: executive summary. A report of the American valve prolapse. Currently, antibiotic prophy- College of /American Heart Association laxis is not recommended for use in patients Task Force on Practice Guidelines (Committee on with mitral valve prolapse in the absence of Management of Patients with Valvular Heart Dis- ease). Circulation 1998;98:1949-84. mitral regurgitation. Only patients with pro- 2. Cheitlin MD, Alpert JS, Armstrong WF, Aurigemma lapsing and regurgitant valves, evidenced by GP, Beller GA, Bierman FZ, et al. ACC/AHA Guide- audible clicks and murmurs or by mitral lines for the Clinical Application of Echocardiogra- phy. A report of the American College of Cardiol- regurgitation demonstrated on Doppler ogy/American Heart Association Task Force on imaging, should receive .6 Practice Guidelines (Committee on Clinical Appli- cation of Echocardiography). Circulation 1997;95: Final Comment 1686-744. 3. Carabello BA, Crawford FA. Valvular heart disease. Great progress has been made in improv- N Engl J Med 1997;337(1):32-41 [published erra- ing rates of morbidity and mortality in tum appears in N Engl J Med 1997;337:507]. 4. Lester SJ, Heilbron B, Gin K, Dodek A, Jue J. The patients with valvular heart disease. Success- natural history and rate of progression of aortic ful management of patients with valvular stenosis. Chest 1998;113:1109-14. heart disease requires an evidence-based 5. Otto CM. Valvular heart disease. Philadelphia: approach to echocardiography and to surgi- Saunders, 1999:118,271. 6. Dajani AS, Taubert KA, Wilson W, Bolger AF, Bayer cal intervention. Echocardiography should A, Ferrieri P, et al. Prevention of bacterial endo- assess not only the valvular lesion but also the carditis. Recommendations by the American Heart compensatory changes of the heart in re- Association. JAMA 1997;227:1794-801. 7. Freed LA, Levy D, Levine RA, Larson MG, Evans JC, sponse to the lesion. Timing of surgical inter- Fuller DL, et al. Prevalence and clinical outcome of vention often correlates with outcome. Most mitral-valve prolapse. N Engl J Med 1999;341(1):1-7. patients with acquired valvular heart disease 8. Gilon D, Buonanno FS, Joffe MM, Leavitt M, Mar- shall JE, Kistler JP, et al. Lack of evidence of an asso- are at risk for developing endocarditis and ciation between mitral-valve prolapse and stroke in should receive prophylactic antibiotics. young patients. N Engl J Med 1999;341(1):8-13.

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