Efficacy and safety of combined aspirin and warfarin therapy after heart valve replacement: a systematic review and meta-analysis of randomized clinical trials

Aim. To conduct a systematic review and meta-analysis of the efficacy and safety of combined oral anticoagulant therapy with vitamin K antagonists (VKA) and antiplatelet therapy with aspirin compared with VKA monotherapy in patients after mechanical valve replacement. Material and methods . We searched the PubMed, Google Scholar databases for studies comparing the risk of thromboembolic events, major bleeding, and mortality in VKA monotherapy versus combined aspirin and VKA therapy in patients with mechanical valve replacement. Results. Eight randomized clinical trials were selected for this systematic review and meta-analysis. In total, 4082 patients were included in the analysis (mean age, 50,8 years, men — 2484 (60,9%)). A meta-analysis showed that the addition of aspirin to VKA, compared with VKA monotherapy, significantly reduced the incidence of thromboembolic events (odds ratio (OR) 0,47; 95% confidence interval (CI): 0,33-0,67; p<0,0001) and mortality (OR 0,58; 95% CI: 0,38-0,88; p=0,01). The risk of major bleeding in the aspirin plus VKA group compared with VKA monotherapy tended to increase, without reaching a significant difference (OR 1,41; 95% CI: 0,99-2,01; p=0,06). Conclusion. The addition of aspirin to VKA, compared with VKA monotherapy, reduces the risk of systemic embolism and death in patients after mechanical valve replacement. At the same time, the risk of major bleeding did not differ between the groups.