Abstract
Between 1976 and 1987, 613 bioprosthetic valves in the mitral position, with a follow up of 2535 patient-years, and 96 bioprosthetic valves in the tricuspid position, with a follow up of 334 patient-years, were implanted at Mitsui Memorial Hospital. Freedom from primary tissue failure (PTF) for mitral position is 96.8±1.0% at 5 years and 69.7±5.1% at 10 years, though for tricuspid position it figures 100% at 5 and 10 years. In adult patients there is no significant difference of freedom from PTF between older and younger generations.
