Ten-year experience with pericardial xenograft valves.

Five hundred fifty-three pericardial xenografts were inserted in 520 patients during a 9-year period at the Fu Wai Hospital in Beijing. The bovine pericardial xenograft was modeled after a similar type of prosthesis manufactured by Shiley Inc. (Irvine, Calif.). The late mortality rate in this series was only 1.8% per annum and the actuarial survival rate was 73.0% +/- 12% at 10 years. There was a very acceptable low incidence of thromboembolism of 0.41% per annum without the need for permanent anticoagulation. This is similar to the clinical reports with other tissue valves. The main question is the durability of the tissue prosthesis or, in other words, the freedom from valve-related clinical complications. In this series, the expected actuarial valve durability rate was 75.0% +/- 8.8% at 10 years. Whether this will continue to hold up over the next follow-up period is unclear. Certainly other tissue prostheses have shown significant degeneration rates beginning after the sixth year that have risen progressively thereafter. In any case, given the relatively low probability of thromboembolic phenomenon without anticoagulation, the trade-off of a prosthesis that may not be as durable as the mechanical ones is certainly acceptable.