Prosthetic Replacement of the Mitral Valve

Mitral valve replacement was carried out in 100 patients with acquired mitral valvular disease. Preoperatively, two patients were in functional class II (NYHA), 64 in class III, and 34 in class IV. Fifty patients had predominant mitral stenosis, and 50 predominant mitral regurgitation. All were studied before operation by right and left heart catheterization, and the clinical and hemodynamic abnormalities were defined in detail and related to the valvular malformation. Seventeen patients died at or shortly after operation; seven others died in the late postoperative period. Operative methods employed, causes of death, and incidence and significance of nonfatal complications are presented. The 76 surviving patients have been followed for intervals of 15 months to 5 years; 47 are asymptomatic (class I), 26 are in class II, and three in class III. Postoperative hemodynamic assessments uniformly demonstrated regression of pulmonary hypertension, and intracardiac pressures and cardiac index were usually normal at rest. Hemodynamic responses to muscular exercise, however, were abnormal in most patients. Mitral valve replacement provides gratifying symptomatic and hemodynamic improvement in patients with mitral regurgitation or calcific mitral stenosis. Because prosthetic valves presently available are responsible for a significant number of late deaths and serious complication, operation is indicated only in severely disabled patients in whom life expectancy is limited.