Performance of a fabricated trileaflet porcine bioprosthesis. Midterm follow-up of the Hancock modified-orifice valve.

ABSTRACT

The fabrication of the Hancock modified-orifice valve raised questions about its long-term durability. Since 1976, 315 patients (206 male, 109 female) with a mean age of 63 years underwent aortic valve replacement with 21 mm (n = 120), 23 mm (n = 153), 25 mm (n = 36), and 27 mm (n = 6) Hancock modified-orifice valves. There were five operative deaths (1.6% mortality). Two hundred sixty-two patients are alive 2 to 117 (mean 53) months postoperatively. Actuarial probability of survival at 96 months was 78% +/- 3%. Two hundred twenty-two survivors are in Functional Class I or II. Forty-three patients have had valve-related complications thromboembolism in 25 (1.9%/pt-yr), primary valve dysfunction in eight (0.6%/pt-yr), and endocarditis in 11 (0.8%/pt-yr). Twelve patients have required reoperation (0.8%/pt-yr) for primary valve dysfunction (four patients), for endocarditis (five patients), and for perivalvular leak (three patients). At 96 months the actuarial probability of freedom from thromboembolism was 87% +/- 3%, from primary valve dysfunction 97% +/- 2%, and from endocarditis 92% +/- 3%. The probability of freedom from all valve-related complications was 78% +/- 4% and from reoperation 94% +/- 2%. The performance of this prosthesis justifies its continued use for aortic valve replacement.