We present herein a review of 95 patients who underwent valve replacement with the CarboMedics (CM) valve prosthesis between April 1990 and December 1992. The operative mortality for the entire group was 4.2%: 0% following aortic valve replacement (AVR), 2.7% following double valve replacement (DVR). All patients were prescribed warfarin and bucolome for anticoagulation, and were followed up for a mean period of 29.9 months. Late mortality was 8.4%; 3.1% following AVR, 10.8% following MVR, and 12.5% following DVR. There were no cases of mechanical prosthetic valve failure, significant hemolysis, infective prosthetic valve endocarditis, or bleeding complications. After 44 months of follow-up, the actuarial freedom from complications was calculated as: thromboembolism, 97.8 +/- 1.6%; valve thrombosis, 97.8 +/- 1.1%; paravalvular leak, 96.7 +/- 1.9%; and reoperation, 98.9 +/- 1.1%. The overall survival rate was 84.3 +/- 6.3% and all survivors showed a significant improvement in NYHA functional class, from 81% in classes III and IV preoperatively to 99% in classes I and II postoperatively. The CM valve exhibited no significant differences in hemolytic parameters or hemodynamic performance after isolated AVR or MVR compared with the similar type of St. Jude Medical bileaflet valve. The evidence provided by the present study therefore suggests that the CM valve prosthesis can achieve excellent mid-term clinical results and hemodynamic performance with a low incidence of thromboembolism and valve thrombosis.