The main purpose of this meta-analysis was to compare the outcomes of patients who randomly received mechanical valves or bioprosthesis, over a long-term clinical follow-up.
We found only three trials meeting our selection criteria with a total of 1229 patients (8069.5 patient-yr). Bleeding was more frequent in patients with mechanical prostheses both after Syr (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 statistically significant with mechanical prostheses in the aortic position (RR = 1.93; IC = [1.36:2.74]; P = 0.0002). Reoperation was significantly more 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 but these results were heterogeneous between mitral and aortic valves. The choice of valve type does not significantly influence survival.
