[Clinical survey of 126 cases with mitral valve prolapse detected at the annual health check-up].

Clinical and echocardiographic survey of mitral valve prolapse (MVP) was performed in 616 cases, which were selected from about 6,000 health check-up. An echocardiographic study revealed MVP in 126 cases. The prevalence of MVP was about 2% (health check-up survey) and 20.5% (echo study). The male and female ratio was 102/24. Frequent premature contractions, isolated atrial fibrillation and an apical systolic murmur were more frequently associated with MVP. Among 13 cases of isolated atrial fibrillation, seven with MVP were permanent, while other six without MVP were transient. Most cases (77%) were asymptomatic. Mild mitral regurgitation proved by auscultation and phonocardiography was observed in only two cases (1.6%), and most of the cases (81%) had no mitral regurgitant signals by a Doppler study.