NATURAL-HISTORY OF MITRAL-VALVE PROLAPSE

To assess the rate and predictors of complications in patients with mitral valve prolapse (MVP), 316 subjects (mean age 42 +/- 15 years) with echocardiographic MVP were followed prospectively for a mean of 102 months: 220 (70%) were women, 225 (71%) had clinically recognized MVP, and 91 (29%) were detected in family studies. During follow-vp, 11 patients (0.4/100 subject-years) required mitral valve surgery, 6 died of cardiac causes (0.2/100 subject-years), 7 developed cerebral ischemia (0.3/100 subject-years), and 2 developed active infective endocarditis (0.1/100 subject-years). The overall rate of fatal and nonfatal complications (1/100 patient-years) was higher in men than in women (odds ratio [OR] 3.2, p < 0.003), in subjects aged >45 than less than or equal to 45 years (OR 3.4, p = 0.002), in clinically recognized patients than in affected family members (OR 3.8, p < 0.02), and in those with a holosystolic murmur (OR 26.9, p < 0.00005); the overall rate was lower in those with a midsystolic click (OR 0.3, p < 0.002). Echocardiographic left ventricular or atrial diameter greater than or equal to 6.0 or greater than or equal to 4.0 cm, respectively, was associated with a 16.7- and 15.1-fold higher likelihood, respectively, of subsequent complications. In conclusion, the risk of morbid and mortal complications of MVP (1) is low (1%/year vs 2% to 4%/year in previous echocardiographic series); (2) is higher in men, older patients, and patients with evidence of significant mitral regurgitation (holosystolic murmurs and left-sided chamber enlargement); and (3) may only be about one fourth as high in unselected patients with MVP (approximated by our family members) as in MVP patients referred to university hospitals.