Warfarin use reduces mortality risk after aortic valve replacement
USA: Warfarin use after bioprosthetic surgical aortic valve replacement (sAVR) was tied to lower all-cause mortality and decreased thromboembolism risk compared with not receiving warfarin, a recent retrospective study has revealed. The findings were published online in Mayo Clinic Proceedings.
The use of bioprosthetic aortic valve replacement has increased significantly during the past decade. Among its advantages is that most patients can avoid warfarin for anticoagulation treatment. Even so, research has been conflicting on whether patients would benefit from more aggressive early postoperative anticoagulation treatment.
The researchers compared thromboembolic events and all-cause mortality in patients undergoing surgical aortic valve replacement receiving anticoagulation with warfarin versus patients with no systemic anticoagulation.
Mayo Clinic researchers analyzed nationwide data on more than 10,000 patients who underwent bioprosthetic aortic valve replacement. Warfarin use was associated with a 32% reduction in mortality risk. Patients treated with warfarin early postoperatively also had an increased risk of major bleeding events.
Key findings:
- Of 10,589 patients having sAVR, 72.3% were in the nonwarfarin group and 27.7% were in the warfarin group. After PS matching, 2930 pairs of patients were analyzed. Median follow-up was 4.1 months for the warfarin group and 21.3 months for the nonwarfarin group.
- Overall mortality was lower for the warfarin group than for the nonwarfarin group (hazard ratio [HR], 0.68), and there was a trend toward decreased cumulative incidence of thromboembolic events (subdistribution HR [SHR], 0.62).
- The cumulative incidence of major bleeding events was higher for the warfarin group vs the nonwarfarin group (SHR, 1.94). Results were similar in a subgroup analysis of patients undergoing isolated sAVR.
"The findings support early warfarin use in appropriately selected patients, such as patients with low bleeding risk," says Hartzell Schaff, M.D., a Mayo Clinic cardiovascular surgeon who contributed to the study. "There’s often reluctance to prescribe anticoagulant treatment early after surgery due to concerns about bleeding and uncertainty about benefits. Our research finds that the small increased hazard of bleeding (4% versus 2.3%) may be an acceptable risk given the benefits in terms of mortality risk as well as reduced risk of thromboembolism."
The Mayo Clinic study analyzed deidentified patient data from 2007 to 2019 using OptumLabs Data Warehouse, which contains claims data of commercially insured and Medicare Advantage enrollees of all ages and races throughout the U.S.
Reference:
Huang Y, Schaff HV, Swarna KS, Sangaralingham LR, Nishimura RA, Dearani JA, Crestanello JA, Greason KL. Benefit of Anticoagulation Early After Surgical Aortic Valve Replacement Using Bioprosthetic Valves. Mayo Clin Proc. 2023 Dec;98(12):1797-1808. doi: 10.1016/j.mayocp.2023.08.012.
