Nonusefulness of Antithrombotic Therapy After Surgical Bioprosthetic Aortic Valve Replacement

Abstract

Controversy persists regarding the advisability of anticoagulation for the early period after biological surgical aortic valve replacement (AVR). We aim to examine the impact of various antithrombotic regimens on outcomes in a large cohort of biological AVR patients. Records of 1,111 consecutive adult patients who underwent surgical biological AVR at our institution between 2013 and 2017 were reviewed. Outcomes included stroke, bleeding, and death at 3 and 12 months. Treatment regimens included (1) no therapy, (2) anticoagulants (warfarin or Factor Xa inhibitors), (2) antiplateles (various), and (4) anticoagulants + antiplatelets. Kaplan-Meier analysis was used to track outcomes, and Cox-proportional hazards regression models were conducted to analyze effects of different therapies on adverse events. At 3 months, thromboembolic events were low and not significantly different between the no therapy group (2.2%) and anticoagulation (2.8%) or anticoagulation + antiplatelet (3.6%) or all groups (3.7%). The antiplatelet group was just significantly lower, at 2.2%. However, this was driven by non-stroke cardiovascular events in patients with coronary artery disease. The incidence of death at 3 months was low and not significantly different between all groups. At 12 months, there were no thromboembolic benefits between groups, but bleeding events were significantly higher in the anticoagulation group (no therapy (1.4%), anticoagulation (8.4%), antiplatelet (4.5%), anticoagulation + antiplatelet (7.9%)). In conclusion, none of the antithrombotic regimens showed benefits in stroke or survival at 3 or 12 months after biological AVR. Anticoagulation increased bleeding events. Routine anticoagulation after biological AVR appears to be unnecessary and potentially harmful.