[Mitral valve prolapse: the clinical and echocardiographic characteristics in a hospital outpatient population].

BACKGROUND: Mitral valve prolapse (MVP) is generally regarded as a benign condition, but serious complications (including severe mitral insufficiency, cerebral ischemia, infective endocarditis, complex arrhythmias and sudden death) have been described in a minority of patients and have been correlated to demographic, clinical and echocardiographic characteristics. Both a lack of standardized definition of MVP in earlier studies and the different ways of recruitment of MVP patients may explain the variability in reported complication rates. METHODS: As an offspring of a larger prospective study this paper focuses on the profile of patients who were found to have MVP by M-Mode and two-dimensional echocardiography in several outpatient hospital departments. A total of 8252 consecutive subjects, examined since March 1990 to February 1991 in the Echo laboratories of the Florence area are considered; according to the presence or absence of structural changes (anterior mitral leaflet thickness > 5 mm, leaflet redundancy and/or anulus dilatation) two groups of patients with MVP (A and B) were identified. RESULTS: A MVP was diagnosed in 288 subjects (3.5%), 170 females (59%) and 118 males (41%), mean age 41 +/- 18 years (range 7-84). 110 (38%) were in Group A, 178 (62%) in Group B. The following parameters differed significantly in the two groups: age (45 +/- 17 vs 39 +/- 17 years; p < 0.003); male gender (50% vs 35%; p < 0.01); auscultatory findings (midsystolic click: 31% vs 68%; p < 0.00001; holosystolic murmur: 22% vs 3%; p < 0.00001); left ventricular diameter (53 +/- 7 vs 48 +/- 5 mm; p < 0.00001) and left atrial diameter (38 +/- 8 vs 33 +/- 5 mm; p < 0.00001). Among patients with mitral regurgitation detected by Color Doppler Echocardiography 65% were in Group A (p < 0.00001). CONCLUSIONS: These patients with MVP are obviously selected by the modality of recruitment; hence there is a higher prevalence of subjects with morphologic abnormalities and mitral regurgitation who are older and more likely to be male if compared to individuals with MVP who are found in the general population. A long-term follow-up of these patients is ongoing: owing to the data of the literature about prognostic predictors, a higher incidence of complications with a different prognosis between the two groups (with or without structural changes of the mitral valve) is expected.