Direct oral anticoagulants versus vitamin K antagonists in the first 3 months after bioprosthetic valve replacement: a systematic review and meta-analysis

OBJECTIVES: We conducted a systematic review and meta-analysis of randomized controlled trials comparing direct oral anticoagulants (DOACs) to vitamin K antagonists (VKAs) in the first 90 days after bioprosthetic valve implantation. METHODS: We systematically searched Embase, Medline and CENTRAL. We screened titles, abstracts and full texts, extracted data and assessed the risk of bias in duplicate. We pooled data using the Mantel-Haenzel method and random effects modelling. We conducted subgroup analyses based on the type of valve (transcatheter versus surgical) and timing of initiation of anticoagulation (<7 vs >7 days after valve implantation). We assessed the certainty of evidence using the Grading of Recommendations, Assessments, Development and Evaluation approach. RESULTS: We included 4 studies of 2284 patients with a median follow-up of 12 months. Two studies examined transcatheter valves (1877/2284 = 83%) and 2 examined surgical valves (407/2284 = 17%). We found no statistically significant differences between DOACs and VKAs with regard to thrombosis, bleeding, death or subclinical valve thrombosis. However, there was a subgroup trend towards more bleeding with DOACs when initiated within 7 days of valve implantation. CONCLUSIONS: In the existing randomized literature on DOACs versus VKAs in the first 90 days after bioprosthetic valve implantation, there appears to be no difference with regard to thrombosis, bleeding or death. Interpretation of the data is limited by small numbers of events and wide confidence intervals. Future studies should focus on surgical valves and should include long-term follow-up to assess any potential impact of randomized therapy on valve durability.