A five year study of the incidence of valve-related complications with the Omniscience cardiac prosthesis.

A total of 228 Omniscience cardiac valve prostheses were implanted in 210 patients at two hospitals in Canada from November, 1979 to August, 1984. The 184 operative survivors were followed for a mean duration of 28.5 months (maximum 62.7 months) and for a total of 438 patient-years. Actuarial analysis for AVR, MVR, and all patients showed survival probabilities at five years of 97.2%, 98.9%, and 97.0% respectively. The five-year actuarial probabilities of remaining free of any thrombotic complications were 96.9% for AVR, 96.4% for MVR, and 95.7% overall. When considering only serious thrombotic complications (thromboembolism with deficit or valve thrombosis), the event-free rates are 100% for AVR, 98.9% for MVR, and 98.6% for the overall patient group at five years. These rates for survival and freedom from thrombotic complication demonstrate the clinical safety and effectiveness of the Omniscience prosthesis. In addition, there were no cases of structural failure or intrinsic mechanical malfunction of the prosthesis.