Background and aims of the study: Extended experiences of the Carpentier-Edwards Supra-Annular Valve (CE-SAV) and the Hancock II (H II) porcine bioprostheses were evaluated to determine the freedom from structural valve deterioration (SVD) by reoperation in the aortic position.
Methods: Between 1981 and 1994, 1,524 procedures (mean patient age 67.6+/-11.2 years) with the CE-SAV, and 670 procedures (mean patient age 65.2+/-12.1 years) with the H II were conducted at the University of British Columbia and University of Toronto, respectively. The patient populations were differentiated by mean age, gender and valve size, but not by concomitant coronary artery bypass. The analyses included actuarial and actual freedom from SVD and evaluation of predictors of SVD.
Results: Actuarial freedom from SVD at 15 years for patients aged > or =65 years was 91.5+/-2.9% for CE-SAV, and 100% for H II (p = NS), while the actual freedom was 96.4+/-1.0% and 100%, respectively. For the patient population aged 66-70 years, the actuarial freedom from SVD was 87.0+/-6.0% for CE-SAV and 100% for H II (p = NS), while the actual rates were 93.6+/-2.3% and 100%, respectively. For the population aged >70 years, the actuarial freedom from SVD was 96.9+/-1.5% for CE-SAV, and 100% for H II (p = NS), while the actual freedom was 98.8+/-0.5% and 100%, respectively. In the patient population aged <65 years, the actuarial freedom from SVD at 15 years favored the H II (p = 0.04), and the actual freedom showed the same outcome. The valve type was not predictive of SVD for age groups < or =60 years, >60 years, 61-70 years and >70 years, but was predictive for the overall population (p = 0.03), as was age and previous valve replacement.
Conclusion: The CE-SAV and Hancock II both provide satisfactory clinical performances, with a low incidence of SVD, and no significant difference in SVD was shown in patients aged > or =65, 66-70, or >70 years. There is a trend to less SVD by actual analysis for the Hancock II in patients aged <65 years. This evaluation must be considered as work-in-progress because of the limited number of patients at risk at 15 years, especially with the Hancock II prosthesis.