Wear in Björk-Shiley heart valve prostheses recovered at necropsy or operation

Thirteen Björk-Shiley prostheses, in situ for up to 27 months, were examined for wear. The discs showed "burnish marks" which did not erode the surface or "wear marks" which did. The metal cages were worn on the "arms" of the inlet strut or at the "hook" of the outlet strut, with metal wear presenting as scored areas or as beveling. This wear is minor and comparable to that seen following accelerated cycle testing in vitro. It is unlikely to seriously affect prosthesis function in the normal lifetime of an individual, but metal wear might cause disc flutter and change auscultatory findings associated with a prosthesis.