[Traumatic mitral insufficiency: a case report].

A 25-year-old man was admitted to Juntendo University Hospital with chief complaints of nocturnal dyspnea and shortness of breath on Sept. 22, 1983. He had no history of rheumatic fever or bacterial endocarditis. He was violently kicked in the chest while practicing Shorinji-Kempo (Karate) in July 1977. His heart murmur was first noticed in April 1978, but he was asymptomatic for six years after the accident until transient nocturnal dyspnea developed January 1983. Physical examination on admission revealed a grade 4/6 apical holosystolic murmur, a markedly accentuated third sound, and hepatomegaly of two finger breadth in the right midclavicular line. An electrocardiogram revealed sinus tachycardia (100/min), left atrial overload and left ventricular hypertrophy. Chest radiography showed slight cardiac enlargement with a cardiothoracic ratio of 55%, and slightly increased pulmonary vascular markings. Two-dimensional echocardiography showed a markedly prolapsed posterior mitral leaflet and fluttering in diastole. Cardiac catheterization showed elevated pressure of pulmonary capillaries (a: 16, v: 30, mean: 19 mmHg), the pulmonary artery and the right ventricle. Left ventriculography revealed grade four (Sellers) mitral regurgitation. Mitral valve replacement was performed on October 13, 1983. A chorda tendinae supporting the posterior leaflet of the mitral valve was found to be ruptured just above its origin from the posterior papillary muscle. Histological examination of the resected valve showed increased spongiosa tissue which mimicked so-called myxomatous changes, but it seemed preferable to interpret this as a "secondary change due to increased hemodynamic stress" rather than the "primary change".