Hypothesis: new concepts on the pathogenesis of early prosthetic valve endocarditis

During the years 1970-1980, 697 patients had valve replacement surgery at our institution. Thirty patients subsequently developed prosthetic valve endocarditis (P.V.E.). Reexamination of the native valves of 25 of these patients revealed histopathological evidence of thromboendocarditis in 7, 5 of whom subsequently developed early P.V.E. In 3 out of 25 matched controls in whom P.V.E. was not diagnosed clinically, similar pathological findings were found; these patients all had fever pre- or post-operatively and were treated with a short antibacterial course, but no definite clinical diagnosis was made. We suggest that there is a close relationship between subclinical thromboendocarditis on the native valve and the early development of infective endocarditis on the implanted artificial valve.