Twelve-year experience with mitral valve replacement.

Between 1962 and 1974, 203 mitral prostheses were implanted in 201 patients. Of the 102 survivors, 29 have Beall, 25 Kay-Shiley, 22 Starr-Edwards (SE) 6000, and 27 SE 6320 valves. Full rehabilitation was achieved in 25 patients with Beall and 23 with SE 6320 valves. Sixteen with SE 6000 valves remain normally active. Only 8 with Kay-Shiley prostheses have resumed normal activities. Systemic embolization occurred with the following frequencies per 1,000 patient-months: 13.7 for those receiving the Kay-Shiley valve; 7.2 in the SE 6000 group; 4.3 after SE 6320 implantations; and 3;1 for the Beall group. Other prosthesis-related complications that were much less frequent included detachment (10), bacterial endocarditis (5), and hemolysis (10). Three Kay-Shiley valves malfunctioned. Life table analyses reveal the following survival rates: 33% after 11 years in the SE 6000 patients, 50% after 7.5 years in the Kay-Shiley group, 69% 2.5 years after SE 6320 implantation, and 65% 3.5 years after replacement with a Beall valve. Evidence is presented to support the extension of operative treatment to patients with less advanced valvular heart disease. Postoperative anticoagulation remains an unresolved issue despite lower rates of thromboembolism. More cumulative analyses of survival and morbidity and follow-up hemodynamic data are needed to assess the Beall and SE 6320 prostheses now employed in our valve replacement program.