AN EXAMINATION OF 2 RETRIEVED LONG-TERM HUMAN IMPLANT BJORK-SHILEY VALVES

Two retrieved long-term human implant Bjork-Shiley valve prostheses we re examined for wear. The prostheses were retrieved at necropsy from a double implant patient that had died from causes unrelated to the val ves twelve years post implantation. Both prostheses were the Bjork-Shi ley conical tilting disc type heart valves with Haynes 25(R) alloy ori fice and a Pyrolite(R) Carbon disc. A size 21 mm valve had been implan ted in the aortic position and a size 27 mm valve had been implanted i n the mitral position. Wear had occurred on the valves in regions of m utual contact between the disc and orifice struts during valve opening and closing. Wear mark depths and types were consistent with previous observations on Pyrolite(R) Carbon Bjork-Shiley and Lillehi-Kaster pr ostheses. No evidence of cavitation nor strut fatigue damage was obser ved on either valve prosthesis. Wear that occurred on the valves was i nsignificant and of no consequence to valve function.