Clinical Outcomes of Anticoagulation Therapy With Direct Oral Anticoagulants or Warfarin in Patients With Atrial Fibrillation and Renal Impairment After Bioprosthetic Valve Replacement.

Background: Atrial fibrillation (AF) after bioprosthetic valve (BPV) replacement is common in older patients with multiple comorbidities and is associated with a heightened risk of thromboembolism. Anticoagulation therapy is often indicated, but renal impairment and other comorbidities elevate bleeding risk, making clinical decisions complex. This study compared clinical outcomes between warfarin and direct oral anticoagulants (DOACs) in this high-risk population. Methods and Results: This subgroup analysis of the BPV-AF Registry included 612 patients treated with oral anticoagulants after BPV replacement, stratified by renal function: normal or mild impairment (creatinine clearance [CCr] ≥50 mL/min), mild-to-moderate impairment (30 mL/min ≤ CCr < 50 mL/min), and moderate-to-severe impairment (15 mL/min ≤ CCr < 30 mL/min). Baseline characteristics and outcomes were analyzed within each stratum. The composite outcome of stroke, systemic embolism, and cardiovascular events was numerically less frequent in the DOAC than warfarin group across all strata, although the differences were not statistically significant. Major bleeding also tended to be lower in the DOAC group. Conclusions: In this study from a Japanese nationwide registry comparing outcomes of AF patients after BPV replacement with severe renal impairment between those treated with DOACs and those treated with warfarin, comparative conclusions between DOACs and warfarin cannot be drawn because of the small sample size. Nonetheless, both anticoagulants may be acceptable in clinical practice, highlighting the need for individualized decision-making based on patient risk.