Mitral valve prolapse and ruptured chordae tendineae

Mechanisms of severe mitral regurgitation in mitral valve prolapse determined from analysis of operatively excised valves

Certain clinical and mitral valvular morphologic findings are described in 83 patients (age 26 to 79 years [mean, 60]; 26 women [31%] and 57 men [69%]) with mitral valve prolapse (MVP) and mitral regurgitation (MR) severe enough to warrant mitral valve replacement. All 83 operatively excised valves were examined by the same person, and all excised valves had been purely regurgitant (no element of stenosis). No patients had hemodynamic evidence of dysfunction of the aortic valve. In each valve a portion of the posterior mitral leaflet was elongated such that the distance from the distal margin to basal attachment of this leaflet was similar to the distance from the distal margin of the anterior leaflet to its basal attachment to the left atrial wall. Two major mechanisms for the severe MR were found: dilatation of the mitral anulus with or without rupture of chordae tendineae and rupture of chordae tendineae with or without dilatation of the mitral anulus. Of the 83 patients, 48 (58%) had both dilated anuli (greater than 11 cm in circumference) and ruptured chordae tendineae; 16 (19%) had dilated anuli without ruptured chordae, and 16 (19%) had ruptured chordae without significant anular dilatation. In three patients the anulus was not dilated, nor were chordae ruptured, and therefore the mechanism of the MR is uncertain. Mitral chordal rupture was nearly as frequent in the 64 patients with clearly dilated anular circumferences as in the 19 patients with normal or insignificantly dilated anular circumferences (less than or equal to 11 cm).

Abnormal chordal insertion: a cause of mitral valve prolapse

Although the morphology of mitral valve prolapse (MVP) has been described, abnormalities of chordal arrangement and insertion have not been emphasized. We retrospectively reviewed 23 surgically-excised MVP and 10 control mitral valves removed at necropsy. Two-dimensional echocardiograms (2DE) were available in 10 MVP and in six additional controls. 2DE accurately assessed the length of anterior leaflet (AL) and posterior leaflet (PL) of the mitral valve (3.2 +/- 0.7 cm and 2.2 +/- 0.6 cm, respectively) as compared to morphologic measurements (3.0 +/- 0.4 cm and 2.1 +/- 0.4 cm, respectively). However, annular diameter as assessed by echocardiography was significantly less (4.6 +/- 0.7 cm) than that derived by morphologic measurements of annular circumference (AC) (5.3 +/- 0.7 cm). The AL and PL lengths and the mitral anuli were significantly larger in patients with MVP as compared to controls (p less than 0.01) when assessed both by 2DE and by morphology. The ratio of the maximum distance of chordal separation/AC was 0.11 +/- 0.04 in MVP and 0.13 +/- 0.02 in controls (p less than 0.05). Chordal divisions were increased in MVP (4.2) compared to controls (3.1, p less than 0.01). The most striking morphologic feature of MVP was abnormal chordal insertion and a random, unpredictable pattern of chordal distribution. We postulate that abnormal chordal architecture may be responsible for unequal stress on the valve leaflets and may thus lead to MVP.

Surgical pathology of the mitral valve: a study of 712 cases spanning 21 years

The gross surgical pathologic features of the mitral valve were reviewed in 712 patients who had undergone mitral valve replacement at our institution during 1965, 1970, 1975, 1980, and 1985. Among the 452 cases of mitral stenosis, either with or without mitral insufficiency, 99% were attributable to postinflammatory disease and 1% were related to congenital mitral stenosis. Among the 260 cases of pure mitral regurgitation, the two most common causes were a floppy valve (38%) and postinflammatory disease (31%). Moreover, a floppy valve was observed in 73% of the 59 examples of chordal rupture and in 38% of the 16 cases of infective endocarditis. Women accounted for 73% of the 452 cases of mitral stenosis and for 72% of the 530 cases of postinflammatory disease. In contrast, men accounted for 58% of the 260 cases of pure mitral regurgitation, including 76% of the floppy valves and 69% of the infected valves. During the 21 years spanned by the study, the relative frequency of postinflammatory mitral insufficiency progressively decreased, whereas that of floppy mitral valves increased. It is unclear whether aging, heredity, environmental factors, changes in the frequency of acute rheumatic fever, or changes in patient referral practices may account for this observation.

Frequency of complications of mitral valve prolapse in subjects aged 60 years and older

One hundred forty-five patients (74 women, 71 men), aged 60 years and older, with echocardiographically documented mitral valve prolapse were studied. One hundred sixteen patients had precordial systolic murmurs, 20 of whom were suspected of having mitral valve prolapse before the echocardiographic study. Infective endocarditis occurred in 7 patients, cerebral ischemic events in 13 and spontaneous rupture of chordae tendineae in 33. Four other patients had ruptured chordae tendineae associated with infective endocarditis. Congestive heart failure was present in 35 patients, 11 of whom had undergone mitral valve surgery.

Prevalence and severity of mitral regurgitation in the mitral valve prolapse syndrome: a Doppler echocardiographic study of 80 patients

Doppler echocardiography was performed in 80 consecutive patients (22 men, 58 women), aged 38 +/- 16 years, who had mitral valve prolapse diagnosed by two-dimensional echocardiography. Of the 80 patients, 16 (20%) were asymptomatic and 11 (14%) had a normal physical examination (no click or murmur). The M-mode echocardiogram was negative for mitral valve prolapse in 11 patients (14%) and equivocal or nondiagnostic in 19 patients (24%). Mitral regurgitation was evaluated using pulsed mode Doppler echocardiography and was quantified by the mapping technique as minimal or mild when a holosystolic regurgitant jet was recorded just below the mitral valve into the left atrium, and as moderate or severe when the jet was detected at the mid- or distal left atrium. Mitral regurgitation was found in 55 (69%) of the 80 patients and it was minimal or mild in 47 patients (59%) and moderate or severe in 8 (10%). In 20 (36%) of the 55 patients with mitral regurgitation by Doppler technique, a systolic murmur was not detected and each of the 20 had only mild mitral regurgitation. Left atrial and left ventricular size were significantly smaller in patients with mild or no regurgitation as compared with the eight patients with moderate or severe regurgitation. These eight patients were all men (six over 50 years of age) who usually presented with dyspnea and a holosystolic murmur; the mitral valve prolapse was holosystolic by M-mode and involved both leaflets by two-dimensional echocardiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Mitral valve prolapse: definition and implications in athletes

Mitral valve prolapse is probably the most common cardiac valve disorder, affecting approximately 5% of the population. Although it is genetically determined, its clinical manifestations do not usually become evident before adulthood. In the setting of a cardiology referral center, a mitral valve prolapse syndrome, consisting of nonspecific symptoms, repolarization changes on the electrocardiogram and arrhythmias, has been identified. However, doubt has recently been expressed about the existence of such a syndrome. The prognosis of mitral valve prolapse is generally favorable but infrequent complications do occur and include transient ischemic attacks, progression of mitral regurgitation with or without ruptured chordae tendineae, infective endocarditis and sudden death. The symptoms and the complications are not usually related to physical activity. A permissive attitude toward participation of patients with mitral valve prolapse in competitive athletics is probably warranted; however, it would appear reasonable to disqualify athletes with mitral valve prolapse in the following circumstances: history of syncope; disabling chest pain; complex ventricular arrhythmias, particularly if induced or worsened by exercise; significant mitral regurgitation; prolonged QT interval; Marfan's syndrome; and family history of sudden death.