Modern anticoagulation strategies in cardiovascular surgery: nonvitamin K antagonist oral anticoagulants versus warfarin after aortic bioprosthetic valve replacement

The optimal postaortic valve replacement (AVR) anticoagulation strategy remains poorly defined, particularly when comparing nonvitamin K antagonist oral anticoagulants (NOACs) versus warfarin. This systematic review and meta-analysis aimed to evaluate the safety and efficacy of NOACs compared with warfarin in these patients. Our study was registered on PROSPERO (ID CRD420251028998). A search of the PubMed, EMBASE, and Cochrane databases was conducted on April 9, 2025, for studies published between 2015 and 2025 that compared NOACs to warfarin after aortic bioprosthetic valve replacement. Inclusion criteria included randomized controlled trials (RCTs) and observational studies reporting thromboembolic events, major bleeding, and mortality with at least 6 months of follow-up. Studies on mechanical valves, case reports, and publications that could not be translated into English were excluded. Data extraction was conducted based on study design, patient demographics, clinical outcomes, and effect sizes, expressed as hazard ratios (HRs) with 95% confidence intervals (CIs) using a random effects model. Risk of bias was assessed using the ROBINS-I tool. Seventeen studies (n = 93,510 participants) were included. NOACs were associated with an HR of 0.91 for thromboembolic events (95% CI: 0.76-1.09) and a pooled HR of 1.22 for major bleeding (95% CI: 0.88-1.68). Several studies have suggested a trend toward lower all-cause mortality and major bleeding with NOACs, particularly in patients with lower bleeding risk. In patients undergoing aortic bioprosthetic valve replacement, NOACs show similar efficacy and safety to warfarin for preventing thromboembolic events and major bleeding. However, anticoagulation decisions should be individualized, and larger RCTs are needed to determine the optimal approach.