Clinical evaluation of the carbomedics prosthesis: experience at providence health system in Portland.

BACKGROUND AND AIMS OF THE STUDY: This study details the authors' experience with the CarboMedics bileaflet mechanical prosthesis, and assesses the valve's efficacy in terms of early mortality and long-term morbidity.

METHODS: Between July 1994 and December 2000, a total of 696 CarboMedics valves was implanted in 616 patients. Aortic valve replacement (AVR) was performed in 350 (57%) patients, mitral valve replacement (MVR) in 161 (26%), double (aortic + mitral) valve replacement (DVR) in 79 (13%), and other procedures in 26 (4%).

RESULTS: There were 32 operative deaths. Operative mortality was 4.3% for AVR, 6.8% for MVR, and 7.6% for DVR. Linearized rates for late death were 3.4%/patient-year (pt-yr), 5.5%/pt-yr and 7.7%/pt-yr for AVR, MVR and DVR, respectively. Survival at five years was 80.1% for AVR, 73.0% for MVR, and 64.6% for DVR (p = 0.004). Freedom from reoperation at five years was 97.6% for AVR, 98.1% for MVR, and 94.1% for DVR (p = 0.718); freedom from thromboembolism at five years was 96.3% for AVR, 98.6% for MVR, and 88.3% for DVR (p = 0.04). Linearized rates of late thromboembolism were 0.7%/pt-yr, 0.4%/pt-yr and 2.3%/pt-yr, respectively. Freedom from PVE at five years was 98.4% for AVR, 97.0% for MVR, and 89.7% for the DVR group (p = 0.172). Linearized rates of PVE were 0.5%/pt-yr, 0.9%/pt-yr and 1.8%/pt-yr, respectively. Freedom from anticoagulant-related bleeding at five years was 98.0% in the AVR group, 97.8% in the MVR group, and 88.3% in the DVR group (p <0.001); linearized rates of this event were 0.4%/pt-yr, 0.6%/pt-yr and 3.2%/pt-yr, respectively. One valve thrombosis was found after MVR, and another in the mitral position after DVR.

CONCLUSION: Early and intermediate-term follow up of the CarboMedics prosthesis indicates that the clinical performance of this valve is satisfactory, and results are comparable with those obtained for other mechanical valves.