MEDIUM-TERM RESULTS OF BIOPROSTHESES IN P ATIENTS OVER 65 YEARS OF AGE

Between 1979 and 1985, 79 patients over 65 years of age (mean 70.8; ra nge 65-82 years) underwent valvular replacement with a bioprosthesis ( aortic: 48, mitral: 26, aortic and mitral: 5). Of the 84 valves implan ted, 56 were porcine and 28 were pericardial bioprostheses. The averag e follow-up was 66 months (total: 434 patient-years; range: 2 months-1 2 years). Twenty-three patients (29 %) died; 13 of these deaths were r elated to the prosthesis and 10 were noe formally related to the biopr osthesis. Of the latter 10 deaths, 7 were caused by malignant disease. Seven patients were reoperated for a complication due to the prosthes is (1.6 % per patient-year): 5 primary tissue failure, 1 endocarditis, 1 perivalvular leak. Sixteen patients (20.3 %) received oral anti-coa gulants for atrial fibrillation; 6 of them (7.6 %) had severe haemorrh agic complications (3 deaths). The actuarial survival was 76.2 % at 5 years and 53.4 % at 10 years. Actuarial survival without reoperation w as 76 % at 5 years and 42 % at 10 years. Analysis of survival with res pect to the type of bioprosthesis (porcine of pericardial), the valve orifice (mitral or aortic) and age (under or over 70 years) did not sh ow 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).