Clinical evaluation of the Omniscience cardiac valve prosthesis. Follow-up of up to 6 years.

Abstract

From January 1984 to June 1989, 259 Omniscience valve prostheses were implanted in 225 patients. Of the 225 patients; 143 (63.6%) received mitral, 48 (21.3%) aortic, and 34 (15.1%) double valve replacements. The early mortality rate was 8.9%; 97.6% of the patients were included in this study. These patients represent a cumulative follow-up of 407.9 patient-years, with a mean follow-up of 2.03 +/- 0.1 (standard error) years. The late mortality rate was 4.03% overall, which corresponds to 2.0% +/- 0.7%/pt-yr (SE). The annual rate of valve endocarditis was 1.0% +/- 0.5%/pt-yr (SE). The linearized rate of thromboembolism was 1.2% +/- 0.5%/pt-yr (SE). Anticoagulant-related hemorrhage occurred in 15 patients with an annual rate of 3.7% +/- 0.9%/pt-yr (SE). The linearized rate of valve thrombosis was 0.2% +/- 0.2%/pt-yr (SE). By echocardiography the mean mitral valve opening was 75.9 +/- 3.1 degrees (standard deviation) for 27 patients. During follow-up study, 136 (70.8%) patients were in New York Heart Association class I, 44 (22.9%) were in class II, and 12 (6.3%) were in class III; there were 25 (11.1%) patients in class II, 166 (73.8%) in class III, and 34 (15.1%) in class IV preoperatively. Actuarial freedom from thromboembolism was 94.5% +/- 3.6% (SE); freedom from endocarditis, 97.8% +/- 1.0% (SE); freedom from anticoagulant-related hemorrhage, 91.5% +/- 2.0% (SE); freedom from valve thrombosis 99.1% +/- 0.8% (SE); and freedom from hemolysis 98.5% +/- 1.2% (SE). Actuarial survival at 6 years is 94.0% + 2.3% (SE) overall. In conclusion, the overall rate of valve-related complications with this valve is low.