Porcine xenograft valves. Long-term (60-89-month) follow-up.

Abstract
An analysis of 211 patients who had porcine xenograft valve replacements at Henry Ford Hospital between October 1971 and March 1974, was accomplished, with 100% follow-up. The follow-up period extended from 60-89 months after implantation. One hundred sixty-seven patients with 192 valves survived the perioperative period and were subjected to life table analysis. Hemodynamically significant porcine xenograft degeneration that required reoperation occurred in 18 patients, two of whom had infective endocarditis. Only four valves failed within 48 months of surgery. Ten of 42 (23.8%) patients with isolated aortic valve replacement and eight of 102 patients (7.8%) patients with isolated mitral valve replacement required reoperation (p < 0.01). In patients under 25 years of age, six of nine surviving patients had repeat operations. Our data indicate that porcine xenograft degeneration is related to the duration of implantation and the age of the patient at the time implantation was performed. In addition, porcine xenograft valves in the aortic position are more likely to degenerate than are those in the mitral position.