CLINICAL-EXPERIENCE WITH THE CARBOMEDICS VALVE - EARLY RESULTS WITH ANEW BILEAFLET MECHANICAL PROSTHESIS

Between January 1989 and August 1992, 612 CarboMedics mechanical prost heses (CarboMedics, Inc., Austin, Tex.) (295 mitral, 308 aortic, and 9 tricuspid) were implanted in 504 patients: 189 patients had isolated mitral valve replacement, 209 had isolated aortic valve replacement, a nd 106 had multiple valve replacement. The total follow-up was 1182 pa tient-years. The hospital mortality rate was 7.4% for mitral valve rep lacement, 5.3% for aortic valve replacement, and 13.2% for multiple va lve replacement. Linearized rates for the different complications for mitral valve replacement, aortic valve replacement, and multiple valve replacement (in events per 100 patient-gears) were, respectively, as follows: late mortality, 2.6 +/- 0.8, 1.5 +/- 0.5, and 3.9 +/- 1.3; th romboembolim, 3.7 +/- 0.9, 3.1 +/- 0.8, and 3.9 +/- 1.3; valve thrombo sis, 0.5 +/- 0.3 for mitral valve replacement and 0.4 +/- 0.4 for mult iple valve replacement; anticoagulant-related hemorrhage, 2.8 +/- 0.8, 1.9 +/- 0.6, and 2.6 +/- 1.1; nonstructural dysfunction, 1.6 +/- 0.6, 0.8 +/- 0.4, and 3.5 +/- 1.2; and reoperation, 1.1 +/- 0.5, 0.4 +/- 0 .3, and 3.1 +/- 1.1. Actuarial estimates of freedom from the different complications for mitral valve replacement, aortic valve replacement, and multiple valve replacement (at 5 years of follow-up for mitral va lve replacement and aortic valve replacement and 4.5 years for multipl e valve replacement) were, respectively, as follows: overall death, 83 % +/- 4%, 89% +/- 2%, and 76% +/- 4%; thromboembolism or valve thrombo sis, 88% +/- 3%, 91% +/- 2%, and 86% +/- 5%; anticoagulant-related hem orrhage, 89% +/- 3%, 95% +/- 2%, and 90% +/- 5%; nonstructural dysfunc tion, 97% +/- 1%, 98% +/- 1%, and 91% +/- 3%; and reoperation, 96% +/- 2%, 99% +/- 1%, and 87% +/- 5%. There were no instances of prosthetic structural dysfunction. The performance of the CarboMedics valve is s atisfactory at 5 years of follow-up but thromboembolic and hemorrhagic phenomena are still serious complications of mechanical prostheses.