Abnormalities in the mitral valve apparatus in patients undergoing long-term hemodialysis. Autopsy and echocardiographic correlation.

Examination of the heart at autopsy in patients who received long-term hemodialysis revealed the following two changes in the mitral valve apparatus previously almost completely overlooked: (1) fibrosis and thickening affecting chordae tendineae in four cases: in one, severe mitral regurgitation was documented by hemodynamic studies; (2) extensive calcification in the mitral anulus region in two cases, with calcification in the base of the mitral leaflets in one and in the papillary muscle and chordae tendineae in the other. The causes of these abnormalities is unclear. Rheumatic and other known causes all seem unlikely origins of the extensive fibrosis. Secondary hyperparathyroidism is probably responsible for the calcification. In all six patients, these abnormalities in the mitral valve apparatus, which may be associated with functional impairment, were diagnosed during life by M-mode and two-dimensional echocardiography.