JACC Vol. 6. No.2 August 1985:475-81

475

Isolated Prolapse of the Tricuspid Valve

DAVID J. WEINREICH, MD, JAMES F. BURKE, MD, FACC, SAROJA BHARATI, MD, FACC,

MAURICE LEV, MD, FACC

Philadelphia, Pennsylvania and Browns Mills, New Jersey

Tricuspid valve prolapse has remained a poorly defined entity. Some authors have stated that prolapse isolated to the tricuspid valve has not been documented. This report contains three cases of isolated tricuspid valve prolapse including the first pathologically confirmed case. A review of worldwide literature including all reported cases of isolated tricuspid valve prolapse is also presented.

Although signs and symptoms are similar to those found with mitral valve prolapse, tricuspid valve pro­lapse may occasionally be differentiated by auscultation. The diagnostic criteria of tricuspid valve prolapse are thoroughly discussed for each of the presently available invasive and noninvasive techniques. Right heart cath­eterization can define such prolapse but is invasive and requires meticulous technique. Two-dimensional echo-

With the widespread use of two-dimensional echocardiog­raphy, a large population with mitral valve prolapse has been identified (1-3). Polyvalvular prolapse with associated involvement of the tricuspid and aortic valves is well de­scribed (4-7). In this report the term isolated tricuspid valve prolapse refers to prolapse involving only the tricuspid valve with or without associated cardiac conditions. Isolated tri­cuspid valve prolapse appears to be rare; indeed, several investigators have stated that it has not been documented (8,9). Our extensive review of the literature revealed only 34 reported cases of isolated tricuspid valve prolapse (Table I) (9-17). The three additional cases described in this report were associated with dilated ischemic cardiomyopathy, hy­pertensive heart disease and chronic lung disease; similar

From the Division of Cardiology, The Lankenau Hospital and the Department of Medicine, Jefferson Medical College of the Thomas Jef­ferson University, Philadelphia, Pennsylvania and the Department of Pa­thology, Congenital Heart and Conduction System Laboratory, Deborah Heart and Lung Center, Browns Mills, New Jersey. This study was aided by Grant HL 30558-02 from the National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland. Manuscript received November 13, 1984; revised manuscript received March 12, 1985, accepted March 29, 1985.

Address for reprints: James F. Burke, MD, Lankenau Medical Build­ing, Suite 239, Lancaster, West of City Line, Philadelphia, Pennsylvania 19151.

(!'l1985 by the American College of Cardiology

cardiography supersedes M-mode because of the supe­rior spatial evaluation of the tricuspid leaflets in relation to the right atrium and ventricle. Multiple views in­cluding a long-axis view of the right ventricular inflow are often required. This parasternal echocardiographic window is often the only one which permits adequate visualization of the posterior leaflet. The pathologic find­ings of tricuspid valve prolapse are similar to those of mitral valve prolapse. This report concludes with a de­scription of associated conditions. Severe tricuspid re­gurgitation has not been noted with tricuspid valve pro­lapse in the absence of superimposed disease, yet much remains undefined concerning the clinical significance of this condition.

(J Am Coil CardioI1985;6:475-81)

associations have been noted previously. In none of these three cases was the condition suspected clinically.

Case Reports Case 1. A 62 year old man had a prior history of inferior

wall myocardial infarction, hypertension and diabetes mel­litus. He was admitted with an acute transmural anterior wall myocardial infarction as evidenced by serial electro­cardiograms. No click or murmur was auscultated. A two­dimensional echocardiogram revealed a very dilated left ventricular cavity, segmental left ventricular dysfunction, anterior hypokinesia and apical dyskinesia compatible with ischemic heart disease. Left ventricular function was mod­erately depressed with an ejection fraction of 36% by the bullet formula (cylinder-cone method). Evaluation of the tricuspid valve showed marked prolapse of the anterior and septalleaftets in the apical four chamber view (Fig. 1). The mitral valve did not show prolapse in multiple views.

Case 2. A 66 year old woman had a 20 year history of essential hypertension. She was admitted to the hospital complaining of blurred vision and uncontrolled hyperten­sion. She had discontinued her antihypertensive medication because of bothersome side effects. Her blood pressure mea-

0735-1097/85/$3.30

476 WEINREICH ET AL. TRICUSPID VALVE PROLAPSE

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Table 1. Reports of 34 Cases of Isolated Tricuspid Valve Prolapse

Author Cases (no.) Method of Diagnosis Associated Conditions

Chandraratna (1975) (II) 4 M-mode echo Coronary artery disease, hypertrophic cardiomyopathy

Maranhao (1975) (10) Brown (1983) (12) Sasse (1978) (13) Horgan (1975) (14) Tei (1983) (15)

9 Catheterization None reported 7 2D echo

M-mode echo None reported Hypertension, sarcoidosis Atrial septal defect M-mode echo

4 2D echo Dilated cardiomyopathy, mitral stenosis, status postatrial septal defect repair

Karayannis (1978) (16) Shimada (1980) (17) Werner (1978) (9)

2 M-mode echo Pulmonary hypertension 2 M-mode echo Chronic lung disease 4 M-mode and 2D echo Right ventricular wound, endocarditis,

pericardial effusion, mitral regurgitation secondary to chordal rupture

Echo = echocardiography; 2D = two-dimensional.

sured 2501150 mm Hg, Funduscopic examination revealed bilateral papilledema and flame-shaped hemorrhages,

Cardiac examination demonstrated a fourth heart sound and a short mid systolic murmur at the left sternal border. Squatting and Valsalva provocative maneuvers failed to elicit any significant change in the duration or intensity of the murmur. No click or regurgitant murmur was present. M­mode and two-dimensional echocardiograms revealed con­centric left ventricular hypertrophy (septal and posterolateral wall thickness of 14 mm with a normal range 9 to II mm on M-mode study),

Systolic buckling of the tricuspid valve was present on M-mode evaluation (Fig, 2), Two-dimensional study re­vealed prolapse of the anterior and septal leaflets of the tricuspid valve into the right atrium, This was evident on both the parasternal right ventricular inflow (Fig. 3) and apical four chamber views. The mitral valve manifested no abnormalities by either M-mode or two-dimensional echocardiography,

Case 3. A 53 year old man had amyotrophic lateral sclerosis for II months and epilepsy for 37 years. In the last several years before his death, he had multiple pul­monary complications including chronic bronchitis and bronchiectasis, Amyotrophic lateral sclerosis was diagnosed clinically. He died from progressive respiratory insufficiency.

At autopsy, the tricuspid valve revealed the following: the anterior leaflet was redundant and irregularly thickened. A small opening whose margins were connected by chordae was present. The medial part of the anterior leaflet was separated from the anterior part of the septal (medial) leaflet by an area measuring approximately 0,5 cm in greatest dimension. No valvular tissue was present in this area, Guarding this area on both sides were aneurysmal dilations or baJloonings and thickening of both the anterior and septal leaflets. The septal and posterior (inferior) leaflets were also redundant and irregularly thickened. The papillary muscle

arrangement of the tricuspid valve was atypicaL The muscle of Lancisi was prominent. The anterolateral papillary mus­cle was normal in position; however, no posterior (inferior) papillary muscle was present. Instead, the posterior and septal leaflets were connected to small nubbins of papillary muscles on the septum in addition to chordae. This abnor­mally formed tricuspid valve was thought to represent the anatomic predisposition for a floppy tricuspid valve. The mitral valve showed no findings of myxomatous degener­ation, In their analysis of 5,467 congenitally abnormal hearts, Bharati and Lev (6) found only this one example of what

Figure 1. Case I, Two-dimensional echocardiogram from the ap­ical four chamber window, Prolapse of the anterior (arrow) and septal leaflets of the tricuspid valve into a normal right atrium (RA) is present Note the presence of marked left ventricular (LV) and left atrial (LA) enlargement along with the clear absence of any degree of mitral valve prolapse. The right atrium and right ventricle (RV) are not markedly dilated,

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Figure 2. Case 2. M-mode echocar­diogram at the level of the tricuspid valve. Systolic sagging of the anterior leaflet is evident (arrow).

was considered to be the pathologic state for isolated tri­cuspid valve prolapse.

In addition to the tricuspid valve findings, right ventric­ular hypertrophy was present. The lungs had diffuse bron­chiectasis with bronchial cysts and mucous plugs accom­panied by bilateral pleural adhesions. Acute passive congestion of both liver and kidneys were present.

Prevalence. The prevalence of mitral valve prolapse in the general population has been reported to be as low as 0.4% (18) or as high as 21% (I). This wide discrepancy may be attributed to a variety of factors including absence of a diagnostic standard, differences in imaging techniques and selective bias in population groups studied. The same problems exist in the diagnosis of tricuspid valve prolapse.

Figure 3. Case 2. Two-dimensional echocardiogram at the level of the right ventricular inflow view. Prolapse of both the anterior and septal leaflets of the tricuspid valve (arrow) into the right atrium (RA) is evident. A thick-walled left ventricular (LV) cavity is present. The septal leaflet (medial in this view) is attached to the anulus at the septum, while the anterior leaflet (lateral) is attached to the right ventricular free wall.

WEINREICH ET AL. 477 TRICUSPID VALVE PROLAPSE

The prevalence of concomitant tricuspid valve prolapse in patients with mitral valve prolapse varies widely among reported series (9,10,12,19-24) and ranges from 5 to 52% (Table 2). Patients with combined mitral and tricuspid valve prolapse tend to be older and more symptomatic than pa­tients with isolated mitral valve involvement (20). Women predominate by a 2: I ratio in isolated mitral valve prolapse and a 3: 1 ratio in combined atrioventricular prolapse (20). Myxomatous valvular degeneration spans all ages; one re­port (25) describes its occurrence in a 3 month old patient.

Symptoms, physical examination and laboratory data. Symptoms of isolated tricuspid valve prolapse are similar to those found in patients with mitral valve prolapse (9,19). These include chest pain, dyspnea and palpitation. In an earlier study from our institution by Mardelli et at. (20), these symptoms were much more prevalent in patients with bivalvular involvement although this finding was re­cently disputed by Schlamowitz et at. (19). Unfortunately, the symptoms in this entity are not at all specific for di­agnosis. The prevalence of symptoms, although possibly increased with bivalvular involvement, is not so markedly

Table 2. Prevalence of Tricuspid Valve Prolapse in 436 Reported Cases of Mitral Valve Prolapse

Prevalence of Cases Tricuspid Valve Method

Author (no.) Prolapse(%) of Diagnosis

Maranhao (1975) (10) 61 52 Catheterization Schlamowitz (1982) (19) 82 50 20 echo Mardelli (1981) (20) 64 48 20 echo Gooch (1972) (21) 13 46 Catheterization Ogawa (1982) (22) 50 40 20 echo Pomerance (1969) (23) 35 26 Pathologic study Brown (1983) (12) 53 25 20 echo Werner (1978) (9) 59 21 M-mode and 20 echo DeMaria (1978) (24) 19 5 20 echo

Abbreviations as in Table I.

478 WEINREICH ET AL. TRICUSPID VALVE PROLAPSE

increased as to permit the clinician to suspect multiple valve involvement by history alone.

Nonejection clicks and mid to late systolic murmurs are the two most common physical findings in both tricuspid and mitral valve prolapse. One study (20) suggested that both the click and the murmur were more common in pa­tients with bivalvular involvement. As with mitral valve prolapse, the timing of the click with tricuspid valve pro­lapse has been found to correlate with maximal prolapse (13). The increase in the degree of prolapse by maneuvers that decrease ventricular filling may aid in the bedside di­agnosis of this disorder (26). Variable hemodynamic loading conditions may produce different degrees of prolapse at different times of examination.

The differentiation of mitral from tricuspid valve prolapse is sometimes possible by auscultation. The click is report­edly more prominent at the lower left sternal border with tricuspid valve prolapse. With inspiration, the click occurs later in systole and often merges with the second heart sound as a result of the increased right ventricular volume.

The systolic murmur with tricuspid valve prolapse may increase in intensity with inspiration despite becoming shorter in duration because of the increased right ventricular filling (10). Like the tricuspid valve click, the murmur is often more prominent at the lower left sternal border. One report (27) claimed success with the use of high-speed echophon­ocardiography to differentiate mitral from tricuspid valve causes of murmurs. Doppler echocardiography may also playa major role in this differentiation.

Skeletal abnormalities including straight back syndrome, scoliosis and pectus excavatum are seen in patients with both mitral and tricuspid valve prolapse. These abnormal­ities may be more common in patients with bivalvular in­volvement (20).

Limited available data suggest that neither the electro­cardiogram nor chest X-ray film provides helpful clues to the diagnosis of tricuspid valve prolapse. The prevalence of repolarization changes, conduction abnormalities and atrial and ventricular arrhythmias was not significantly different in patients with combined mitral and tricuspid valve prolapse compared with patients with isolated mitral valve prolapse (20). With isolated tricuspid valve prolapse, electrocardio­graphic and roentgoenographic abnormalities are more likely attributed to associated cardiac conditions (16). In five pa­tients with both mitral and tricuspid valve prolapse, no ST changes diagnostic of ischemia occurred with exercise stress testing (21). The value of exercise testing in patients with isolated tricuspid valve prolapse is unknown.

Angiography. Gooch and Maranhao and their cowork­ers (10,21) have demonstrated the value of right heart cath­eterization in the evaluation of tricuspid valve prolapse. For right ventriculography, the patient is generally placed in a 5 to 25° right anterior oblique position to eliminate super­imposition of the tricuspid valve over the spine. Right atrial

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dye injection usually provides inadequate visualization (10). The catheter tip is best placed in the right ventricular inflow tract. This more proximal injection generally permits clear visualization of the ventricular surface of the tricuspid valve for at least one full cardiac cycle (14). In this position, arrhythmias may be less easily induced. Deep inspiration is not recommended for this injection because of catheter dis­lodgment resulting in arrhythmias or intramyocardial injec­tion. A lower pressure injection is generally recommended for similar reasons (10).

With the use of proper technique, the normal tricuspid valve projects as either a reversed "c" configuration or a vertical straight line with or without mild serrations (Fig. 4A) (10). With tricuspid valve prolapse, the leaflets bulge into the right atrium in late systole (Fig. 48). Catheter­induced regurgitation is characterized by: a) catheter en­croachment against the leaflet; b) presence of a jet at the catheter site; and c) the occurrence of regurgitation in early systole before maximal valve prolapse. Hemodynamic changes of tricuspid regurgitation, such as right atrial enlargement or prominent "v" waves, are unusual with tricuspid valve prolapse.

Compared with other techniques, angiography is not a preferred method for the diagnosis of tricuspid valve pro­lapse because of the risks of right heart catheterization and the problem of catheter-induced leaflet distortion and regurgitation.

M-mode echocardiography. M-mode and two-dimen­sional echocardiography have contributed greatly to our ap­preciation of normal tricuspid valve motion and its aber­ration with prolapse. M-mode echocardiography has demonstrated a variable spectrum of prolapse of myxoma­tous valves ranging from early, mid, late and pansystolic sagging of the valves (28). The anterior and septal leaflets of the tricuspid valve can be visualized with an M-mode transducer placed in the third or fourth left intercostal space (11 , 13). Transducer angulation is more medial, also often caudal and posterior, compared with mitral valve evalua­tion. The septal leaflet is less well visualized from this approach. Normally, the tricuspid leaflets show a gradual anterior displacement during diastole with M-mode echo­cardiography. To establish the diagnosis of tricuspid valve prolapse, one of the following criteria must be present 1) pansystolic sagging with posterior displacement of at least 2 mm below the C-D line; or 2) midsystolic buckling with posterior displacement of the tricuspid valve leaflet (Fig. 2). For this M-mode diagnosis, the recording should be reproducible enough so that at least three beats demonstrate the abnormality (9). These M-mode requirements for the diagnosis of prolapse are identical to those of mitral valve prolapse.

Several problems limit the usefulness of M-mode echo­cardiography in the diagnosis of tricuspid valve prolapse. In many patients, the M-mode recording of the anterior

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Figure 4. A, Right ventriculography in a patient with a normal tricuspid valve; note the reversed "c" configuration. B, Right ventriculography in a patient with tricuspid valve prolapse; note the bulging of the leaflets (arrows) into the right atrium beyond the anular ring. RV = right ventricle. (Reprinted with permission of the New England Journal of Medicine from Gooch AS et al. [21 ]).

leaflet of the tricuspid valve is technically difficult and can­not be accomplished. The septal, and particularly the pos­terior, leaflets are exceedingly difficult to visualize. If pro­lapse is isolated to one of these nonvisualized leaflets, the diagnosis will be missed. Angulation errors resulting in shortening of the anulus are easily produced and result in normalization of tricuspid leaflet motion (9). Angulation errors are more easily recognized by two-dimensional than by M-mode echocardiography.

Two-dimensional echocardiography. Compared with M-mode echocardiography, the two-dimensional technique can better permit spatial evaluation of the tricuspid leaflets in relation to the right atrium, right ventricle and tricuspid anulus. Although multiple echocardiographic windows and

WEINREICH ET AL. 479 TRICUSPID VALVE PROLAPSE

tomographic sections have been described for tricuspid valve assessment, we will restrict our discussion to those views most helpful in the assessment for prolapse.

The essential criterion for diagnosis is leaflet prolapse beyond the anular ring into the right atrium. This anular ring is often difficult to define but is best approximated by the basal attachments of the three leaflets. False positive diagnosis of prolapse results most commonly from inade­quate visualization of the entire valve apparatus with leaflet foreshortening. False negative diagnosis is most often sec­ondary to angulation problems causing distortion, often foreshortening of the anulus (19). Besides buckling of the leaflets into the right atrium in systole, other criteria may alert the echocardiographer that prolapse is present. These include leaflet redundancy and thickening, eccentric coap­tation, anular dilation (15) and diminished change in anular size from diastole to systole (29).

A right ventricular inflow view can be obtained from the parasternal position in the third or fourth left intercostal space (Fig. 3) (30). The anterior leaflet is longer and at­tached to the right ventricular free wall. The septal leaflet is attached to the interventricular septum; though shorter, it is the most commonly visualized leaflet in this view (12). The posterior leaflet is not generally seen in this location (9).

The apical four chamber view is the other commonly used view for analysis of tricuspid leaflet motion (30). Slight medial angulation is desirable to optimize tricuspid valve visualization. In this view, the relation between anulus and leaflets is often easily appreciated. The tricuspid anulus is more apically located than the mitral one. The septal leaflet is medial and the anterior leaflet is lateral (Fig. I). The posterior leaflet is again not generally seen.

With subxiphoid placement of the transducer. a four chamber view may be obtained (30). Patients with hyper­inflated lungs, resulting in impairment of the parasternal and apical echocardiographic views, often have satisfactory studies performed with this sub xiphoid window. The anterior leaflet is the one best visualized with this view (12).

A long-axis plane of the right ventricular inflow tract can provide tomographic cuts critical to the assessment of the tricuspid valve for prolapse (15,29). This is generally the only echocardiographic plane that permits optimal visual­ization of the posterior leaflet (Fig. 5).

Using these multiple views. all three leaflets may be vis­ualized in 75% of patients (12). In patients with tricuspid valve prolapse, the septal leaflet is involved in 93% of cases compared with 86 and 43% for the anterior and the posterior leaflets, respectively (15).

Pathology. Similar to mitral valve prolapse, tricuspid valve prolapse may be defined as "sufficient elongation of chordae and expansion of cusp area to allow prolapse into the atria on applying a pressure load to close the valve" (31).

480 WEINREICH ET AL. TRICUSPID VALVE PROLAPSE

Figure 5. Two-dimensional echocardiogram of the long-axis right ventricular (RV) inflow view. This echocardiographic plane per­mits optimal visualization of the anterior and posterior (long ar­row) tricuspid leaflets. Note the aortic ring (short arrow) adjacent to the anterior leaflet as well as the nonvisualization of the mitral valve and tricuspid septal leaflet in this plane. Prolapse was not noted in either leaflet in this patient with known right atrial (RA) and ventricular enlargement.

Macroscopically, tortuosity and thickening resembling rheumatic valvulitis are present. The atrial side of the leaflet frequently appears opacified with secondary fibrosis. Con­fusion with rheumatic involvement of both the leaflet and chordae is easily avoided by noting the presence of chordal and leaflet elongation as opposed to their shortening in the rheumatic tricuspid valve (31). We previously reported (6) the irregular thickenings and nodular formations of the myxomatous valves in patients with polyvalvular involve­ment. In this case report of pathologically determined iso­lated tricuspid valve disease with presumed prolapse, many of these features including voluminous leaflets with irregular surface thickenings were present.

Microscopically, the dense core of the floppy valve shows loss of fibrous tissue, fragmentation and coiling of individual collagen bundles (31). Myxomatous degeneration refers to the destruction of collagen in association with the accu­mulation of pools of acid mucopolysaccharide. The prolif­eration of the spongiosa is associated with hypoeiastification and even disruption of the normal architecture (6). In con­trast to other hereditary forms of collagen disorders, ab­normal periodicity of the collagen bundles is not seen (31). The atrial surface of the leaflet commonly reveals areas of fibrous deposi~s (23). The inflammatory cells typically seen with rheumatic tricuspid involvement are generally not pres­ent (31).

Associated conditions and clinical significance. Numerous theories have been proposed to explain the patho­logic changes in tricuspid valve prolapse. These include

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congenital anomaly, underlying stress or hemodynamic tur­bulence, myocardial ischemia or infarction, systolic dys­function of the right ventricle or degeneration as part of an aging process (23). Autopsy series (31) tend to show a higher incidence of tricuspid valve prolapse in patients with more advanced degrees of mitral valve prolapse. Polyval­vular involvement, presumably congenital in origin, has been reported (6). Prolapse of both atrioventricular valves has also been reported (9, II ,32) with Marfan's syndrome, idiopathic hypertrophic subaortic stenosis, Ebstein's anom­aly, atrial septal defect and mitral regurgitation with chordal rupture.

Some series (10,12) do not describe associated cardiac disorders with the isolated tricuspid valve prolapse. Those cases with associated conditions fall into three categories (Table 3). Many of the patients with isolated tricuspid valve prolapse have primarily left ventricular abnormalities. This group includes patients with dilated cardiomyopathy, sys­temic hypertension and mitral regurgitation (9,13,15). In our Cases I and 2, in which the diagnosis was made on echocardiography, the left ventricle showed marked abnor­malities: cavity dilation in Case I and concentric left ven­tricular hypertrophy in Case 2. The second group with iso­lated tricuspid valve prolapse includes those patients with a pressure load on the right heart chamber. This group includes patients with puhllonary hypertension, either idio­pathic or secondary to chronic obstructive lung disease, or pulmonary emboli (16, 17). Other disease entities in this second group include atrial septal defect, mitral stenosis and pericardial effusion (9,10,14,15). Our Patient 3 had ad­vanced lung disease. Finally, isolated tricuspid valve pro­lapse has been reported in two patients with direct injury to the valvular apparatus, one due to endocarditis and the other from right ventricular trauma (9).

The clinical signifi~'ance of tricuspid valve prolapse will require further long-term follow-up. Like mitral valve pro­lapse, chest pain syndrome and other symptoms may occur. Endocarditis and pulmonary emboli have been associated with tricuspid valve prolapse (9,16,33,34). It remains un-

Table 3. Associated Conditions With Isolated Tricuspid Valve Prolapse

I. Left ventricular abnonnalities Dilated cardiomyopathy Systemic hypertension with presumed hypertensive heart disease Mitral regurgitation due to chordal rupture

2. Right heart pressure increase Pulmonary hypertension: idiopathic or secondary to chronic

obstructive pulmonary disease, pulmonary emboli Atrial septal defect Mitral stenosis, possibly with pulmonary hypertension Pericardial effusion

3. Direct valvular injury Endocarditis Right ventricular trauma

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resolved whether patients with bivalvular prolapse have a greater predisposition to malignant arrhythmias and sudden death. Tricuspid regurgitation has been demonstrated in pa­tients with tricuspid valve prolapse by angiographic and contrast two-dimensional echocardiographic techniques (10,35). A 40% prevalence of tricuspid regurgitation has been reported (35). With the enhanced sensitivity using Doppler echocardiography in the detection of regurgitant lesions, this technique holds great promise as a diagnostic aid for this condition. The tricuspid regurgitation associated with prolapse is mild or moderate (10). We are not aware of any patient who has required tricuspid valve replacement in the absence of a secondary process such as endocarditis. Some reports (5,36) have suggested that the incidence of severe mitral regurgitation requiring mitral valve replace­ment may be greater in those patients with bivalvular prolapse.

We acknowledge the following for their invaluable assistance in the prep­aration of this manuscript: Betsy LeFevre. Rose Marie Wells. lanice Tal­bot. Kathleen Elkins and Anne Owens.

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