[Acute surgery-requiring mitral valve insufficiency caused by rupture of the chordae tendineae].

The etiology of acute severe mitral incompetence resulting from rupture of the chordae is presented and is illustrated by four case reports. The condition was incorrectly diagnosed and treated primarily as pneumonia or obstructive pulmonary disease. The correct diagnosis was established primarily by echocardiography. Treatment was surgical with implantation of a mitral valvular prosthesis. In three out of four patients, myxomatously degenerated tissue and balooning of the edges of the cups, compatible with the diagnosis of the mitral prolapse syndrome were found. The pathogenesis appears to be primarily dysplasia of the chordae with a component of mechanical wear and tear with physical exertion as the factor precipitating the rupture. The diagnosis of severe mitral incompetence resulting from rupture of the chordae should be borne in mind in cases of acutely developing dyspnoea.