Comparison of bioprosthesis and mechanical valves, a meta-analysis of randomised clinical trials

The main purpose of this meta-analysis was to compare the outcomes of patie nts who randomly received mechanical valves or bioprosthesis, over a long-t erm clinical follow-up. We found only three trials meeting our selection cr iteria with a total of 1229 patients (8069.5 patient-yr). Bleeding was more frequent in patients with mechanical prostheses both after 5 yr (RR = 2.6; IC = [1.9;3.5]; P < 0.0001) and 11 yr (RR = 1.6; IC = [1.2;2.2]; P < 0.001 ) of follow-up. However, the increased risk of bleeding at 11 yr was only s tatistically significant with mechanical prostheses in the aortic position (RR = 1.93; IC = [1.36:2.74]; P = 0.0002). Reoperation was significantly mo re frequent in patients with bioprosthesis after 11 yr follow-up (RR = 0.4; IC = [0.3;0.6]; P < 0.001). Endocarditis was more frequent after 11 yr (RR = 0.6; IC = [0.3;0.95]; P < 0.05) in patients with mechanical prostheses b ut these results were heterogeneous between mitral and aortic valves. The c hoice of valve type does not significantly influence survival. (C) 2000 The International Society for Cardiovascular Surgery. Published by Elsevier Sc ience Ltd. All rights reserved.