Over twenty-year follow-up of the standard Hancock porcine bioprosthesis implanted in the mitral position

Background. To define the long-term results of 331 standard Hancock porcine bioprostheses implanted in the mitral position between 1973 and 1980. Methods. Of 331 patients (225 male patients, 68%), mean age 49 +/- 10 years (range 14 to 69 years), 88% were in New York Heart Association functional class III or IV and 77% were in atrial fibrillation. Follow-up time extende d more than 20 years (mean 13.9 years, range 0.3 to 24.7 years) for a total of 4,601 patient-years. Results. Overall operative mortality was 6.3%. At 5, 10, 15, and 20 years, the actuarial survival rate of patients were 71% +/- 2%, 46% +/- 3%, 30% +/ - 3%, and 22% +/- 2%, respectively. Actuarial estimates of freedom from str uctural valve deterioration were 95% +/- 1%, 67% +/- 3%, 32% +/- 3%, and 14 % +/- 3%; from reoperation were 96% +/- 1%, 72% +/- 3%, 36% +/- 4%, and 18% +/- 4%; from thromboembolism were 89% +/- 2%, 82% +/- 3%, 74% +/- 4%, and 51% +/- 2%; and from anticoagulant-related hemorrhage were 98% +/- 1%, 96% +/- 1%, 91% +/- 1%, and 86% +/- 4%. Estimates of freedom from all valve-rel ated mortality at 5, 10, 15, and 20 years were 89% +/- 2%, 76% +/- 3%, 64% +/- 4%, and 48% +/- 4%. Multivariate analysis showed younger age to be a si gnificant risk factor for reoperation. Age at operation did not correlate w ith structural valve deterioration. Conclusions. The long-term results with the standard Hancock bioprosthesis implanted in the mitral position appear satisfactory, particularly up to 15 years from implantation. Protection from stroke, anticoagulant hemorrhage, and endocarditis was good. (C) 2001 by The Society of Thoracic Surgeons.