Clinical spectrum and long-term follow-up of isolated mitral valve prolapse in 119 children.

One-hundred nineteen children with isolated mitral valve prolapse were studied in order to elucidate the clinical, electrocardiographic, echocardiographic, angiographic and exercise response manifestations and its natural history in childhood. The mean age at the time of diagnosis was 9.9 years, with a mean follow-up of 6.9 years. The diagnosis in 118 cases was based on characteristic auscultatory phenomena. Ninety-one percent (n = 84) of the patients undergoing echographic examination had documentation of mitral valve prolapse. The evaluation of these children also included routine ECGs (n = 116), thoracic roentgenograms (n = 106), cardiac catheterization (n = 16), and graded exercise testing (n = 43). Two patients required antiarrhythmic medication for supraventricular tachycardia. No progression of mitral incompetence was observed, and there were no sudden deaths. One patient developed infective endocarditis and one had a cerebrovascular accident. We conclude that the diagnosis of mitral valve prolapse can be made clinically by characteristic auscultatory phenomena and that "silent" mitral prolapse is rare in childhood. The prognosis of isolated mitral valve prolapse in children appears to be excellent.