[Mid-term results of bioprosthesis in patients over 65 years].

Between 1979 and 1985, 79 patients over 65 years of age (mean 70.8; range 65-82 years) underwent valvular replacement with a bioprosthesis (aortic: 48, mitral: 26, aortic and mitral: 5). Of the 84 valves implanted, 56 were porcine and 28 were pericardial bioprostheses. The average follow-up was 66 months (total: 434 patient-years; range: 2 months-12 years). Twenty-three patients (29%) died; 13 of these deaths were related to the prosthesis and 10 were not formally related to the bioprosthesis. Of the latter 10 deaths, 7 were caused by malignant disease. Seven patients were reoperated for a complication due to the prosthesis (1.6% per patient-year): 5 primary tissue failure, 1 endocarditis, 1 perivalvular leak. Sixteen patients (20.3%) received oral anti-coagulants for atrial fibrillation; 6 of them (7.6%) had severe haemorrhagic complications (3 deaths). The actuarial survival was 76.2% at 5 years and 53.4% at 10 years. Actuarial survival without reoperation was 76% at 5 years and 42% at 10 years. Analysis of survival with respect to the type of bioprosthesis (porcine of pericardial), the valve orifice (mitral or aortic) and age (under or over 70 years) did not show any significant differences. Follow-up of patients over 65 years of age showed a high rate of haemorrhagic complications related to oral anticoagulant therapy for atrial fibrillation (6.8% per patient-year), a low rate of primary tissue failure (1.1% per patient-year) and a low reoperative mortality (1 death for 7 reoperations).