Direct oral anticoagulants for atrial fibrillation in early postoperative valve repair or bioprosthetic replacement.

OBJECTIVE: Despite increased use of direct oral anticoagulants (DOACs), limited evidence guides their use in the early postoperative period after bioprosthetic valve implantation in patients with atrial fibrillation. Our objective was to describe the efficacy and safety of DOACs and warfarin in the first 3 months after surgical bioprosthetic valve replacement or repair in patients with atrial fibrillation. METHODS: This was a retrospective, registry-informed cohort study of surgical patients who underwent bioprosthetic valve replacement or repair, had concomitant atrial fibrillation and received oral anticoagulation at discharge. The primary efficacy outcome was a composite of death, ischemic stroke, transient ischemic attack, and systemic embolism; the primary safety outcome was a composite of major bleeding. Key secondary outcomes were comparative analyses of primary outcomes, temporal anticoagulation prescribing patterns, and 30-day readmission rates. RESULTS: A total of 1743 patients were included. Of the 570 patients in the DOAC group, 17 (2%) met the composite efficacy outcome and 55 (10%) met the composite safety outcome. Of the 1173 patients receiving warfarin, 41 (3%) and 114 (10%) met the composite efficacy and safety outcomes, respectively. Comparative secondary analysis was not statistically significant for either the efficacy (adjusted odds ratio, 0.85; 95% confidence interval, 0.46-1.55, P = .59) or safety (adjusted odds ratio, 0.94; 95% confidence interval, 0.66-1.34, P = .76) outcomes. The 30-day readmission rates were similar between both groups. CONCLUSIONS: Our results suggest DOACs may be safe and effective alternatives to warfarin in the early postoperative period after valve repair or surgical bioprosthetic replacement. Confirmation awaits adequately powered prospective studies.

Mechanical Mitral Valve Thrombosis Secondary to Tinzaparin as an Anticoagulation Bridging Strategy.

For patients with mechanical heart valves, oral vitamin K antagonists effectively reduce the risk of valve thrombosis. Bridging strategies that use intravenous unfractionated heparin or subcutaneous low molecular weight heparin (LMWH) are required when reversal of anticoagulation is needed for invasive procedures or bleeding complications. There is limited data comparing anticoagulation efficacy between subtypes of LMWH and dosing regimens in this context. This report describes the case of a 45-year-old man with acute mechanical mitral valve thrombosis and suggests that the use of once daily dosing of subcutaneous tinzaparin may be an inappropriate anticoagulation bridging strategy.