title: Long term results of 212 xenograft valve replacements.
mesh_terms: D000818:Animals; D001021:Aortic Valve / Q000637:transplantation*; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D006801:Humans; D013552:Swine; D014183:Transplantation, Heterologous