Persistence of Aortic-Valve Homografts

Pathology of the formalin-treated heterograft porcine aortic valve in the mitral position

“…Collagen possesses a low antigenicity. Hirsch (1967) suggested that autograft, homograft, and heterograft valves should all behave similarly in failing to evoke a destructive immunological or inflammatory response in the host. Our findings in 9 of the 11 valves confirm this with regard to heterograft valves.…”