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

Abstract

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 re- quired 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.THE CLINICAL FEATURES of mitral valve prolapse (MVP) have been well described in adults,1'3 but little attention has been given to the spectrum of isolated MVP in children.4 7 We identified 118 children with the characteristic auscultatory features of MVP and one child with echocardiographic manifestations of prolapse, but an absence of clinical findings.In this study we analyze the clinical, electrocardiographic, echocardiographic, angiographic findings, exercise response, and natural history in these patients with MVP. Materials and MethodsOne hundred eighteen patients seen at Children's Hospital Medical Center had auscultatory evidence of a late systolic murmur, apical systolic nonejection click, or both.This study group represents all of the children referred to our institution between 1956 and 1977 who were recognized as having isolated MVP.Auscultation was performed in every case with the patient in the supine, left lateral decubitus, standing and squatting positions.The timing and intensity of the murmur/click complex responded charac- teristically to various postural maneuvers.8'B In every instance the patients were examined by one of the in- vestigators.We excluded from the study all patients with hypertrophic cardiomyopathy, pericardial effusion, atrial septal defect (ASD), ventricular septal