Long-term results of aortic valve replacement with nonviable homografts

Between 1965 and 1972, 250 patients (186 men and 64 women; median age, 48 years) underwent aortic valve replacement with homografts preserved with beta-propiolactone (98 patients) or irradiation (152 patients); operative mortality was 6% (15 patients). Follow-up to death, reoperation, or recent evaluation was completed in 95% of patients, and median follow-up time was 11.4 years. Thromboembolic events occurred in two patients (0.21 events/100 patients/yr). Risk of reoperation was 22% at 5 years, 62% at 10 years, 85% at 15 years, and 95% at 20 years. Factors associated with increased risk of reoperation were young age, male sex, native aortic valve insufficiency, previous aortic valve surgery, history of endocarditis, and larger homograft size. Survival at 5, 10, 15, and 20 years was 85%, 66%, 53%, and 38%, respectively. Late survival was diminished in older patients and those with native aortic valve insufficiency and coronary artery disease. Aortic valve replacement with nonviable homografts has a high risk of late tissue degeneration and need for reoperation. However, the incidence of thromboemboli is minimal, and grafts can be replaced with low risk (4.5%) so that overall patient survival is similar to that observed with other bioprosthetic or mechanical heart valves.