[Morbidity and mortality seen in patients with a Hancock bioprosthesis, followed for more than 5 years. Experience at the La Pitié Hospital].

Between 1975 and 1983, 305 Hancock bioprostheses were implanted at the La Pitié Hospital, Paris, including 133 on the aortic valve and 172 on the mitral valve. The operative mortality rate was 6 p. 100 in patients with isolated aortic valve replacement and 12.8 p. 100 in patients with isolated mitral valve replacement (including 4 reoperations for mechanical valve thrombosis). 245 patients were followed up for a mean period of 5 1/2 years. The actuarial survival rate, operative mortality excluded, was 77.5 +/- 4.4 p. 100 in the aortic valve group and 76 +/- 4.4 p. 100 in the mitral valve group (non significant difference). Later after surgery, 8 embolic accidents (5 in the mitral valve group, 3 in the aortic valve group) occurred, and 20 patients developed endocarditis. Forty-nine patients required reoperation, 33 of them for deterioration of the bioprosthesis. The probability of being free from such deterioration varied significantly according to the patient's age at the time of the operation. In the aortic valve group this probability at 8 years was 97 p. 100 +/- 2.7 p. 100 for patients over 35 and 63.3 p. 100 +/- 1.7 p. 100 for patients under 35; the corresponding figures at 8 years in the mitral valve group were 80 p. 100 +/- 3.8 p. 100 for patients over 35 and 55.2 p. 100 +/- 2.2 p. 100 for patients under 35. There was no significant difference between the mitral and the aortic valve groups with regard to the percentage of prosthetic valve deterioration. The operative mortality rate in reoperations was 14.2 p. 100 irrespective of the cause of death.