INFLUENCE OF CORONARY-ARTERY DISEASE ON STRUCTURAL DETERIORATION OF PORCINE BIOPROSTHESES

The number of patients undergoing valve replacement and concomitant coronary artery bypass grafting (CABG) is increasing. To further evaluate the indications for the use of the porcine bioprosthesis, this retrospective comparative analysis of valve structural deterioration was conducted in patients with and without concomitant CABG. From September 1974 to October 1993, 1,567 patients underwent valve replacement using a porcine xenograft. The series was divided into two groups: patients with isolated valve replacement (VR; n = 876) and those with VR and CABG (VR + CABG; n = 691). Aortic valve replacement was performed in 938 patients, mitral valve in 518, tricuspid in 2, and multiple valve replacement in 109 patients. The mean age for the series was 70.7 years (range, 50 to 104 years). The hospital mortality was 8.8% (138 patients). The hospital mortality for the VR group was 7.4% (65 deaths) and the VR + CABG group, 10.6% (73 deaths) p = 0.0365. There were 1,429 patients discharged from the hospital with 1,489 valves at risk. Follow-up extended from 1 month to 17.9 years with a mean of 66.9 months and was 98.3% complete. The cumulative follow-up was 7,927.1 patient-years. Structural deterioration was found to be significantly greater in the VR group for the age category 50 to 59 years (p = 0.0121) and the 60 to 69 years (p = 0.0230). No significant difference in the rate of structural deterioration was found for the two groups for the age category 70 years and older. Valve site was found to influence structural deterioration in the age category 60 to 69 years for the VR group (p = 0.0206) and for the age category 70 years and older for the VR group (p = 0.0206) and the VR + CABG group (p = 0.0156). The frequent concurrence of CABG with valve replacement and the clinical observation that porcine xenografts last longer in patients with coronary artery disease substantially affects the indication for their use in patients less than 70 years of age.