The Carpentier-Edwards standard porcine bioprosthesis was implanted in 1,195 patients in 1,213 operative procedures between 1975 and 1987, with the majority of implants performed prior to 1982 at the University of British Columbia. The mean age of the patient population was 57.2 years (range 8 to 85 years). The mean follow-up was 7.4 years per patient. The freedom from the combination of thromboembolism and antithromboembolic therapy-related hemorrhage at 15 years was 79.5% for aortic valve replacement (AVR), 72% for mitral valve replacement (MVR), and 84% for multiple valve replacement (MR) (p less than 0.05, AVR greater than MR greater than MVR). The freedom from structural valve deterioration at 15 years was 71% for AVR, 41% for MVR, and 41% for MR (14 years) (p less than 0.05, AVR greater than MVR greater than MR). The freedom from nonstructural dysfunction and prosthetic valve endocarditis did not distinguish the valve positions (p = NS). The freedom from valve-related mortality from all causes including reoperation was 92% for AVR, 78% for MVR, and 77% for MR at 15 years (p less than 0.05, AVR greater than MVR greater than MR). The freedom from residual morbidity was not significantly different between valve positions (p = NS). The freedom from treatment failure (valve-related mortality and residual morbidity) at 15 years was 87% for AVR, 72% for MVR, and 75% for MR (p less than 0.05, AVR greater than MR greater than MVR). The freedom from all complications at 14 years was 50% for AVR, 25% for MVR, and 27% for MR (p less than 0.05, AVR greater than MR greater than MVR).(ABSTRACT TRUNCATED AT 250 WORDS)