Long-Term Anticoagulation Discontinuation After Catheter Ablation for Atrial Fibrillation: The ALONE-AF Randomized Clinical Trial

Importance: Data from randomized clinical trials on a long-term anticoagulation strategy for patients after catheter-based ablation for atrial fibrillation (AF) are lacking. Objective: To evaluate whether discontinuing oral anticoagulant therapy provides superior clinical outcomes compared with continuing oral anticoagulant therapy in patients without documented atrial arrhythmia recurrence after catheter ablation for AF. Design, Setting, and Participants: A randomized clinical trial including 840 adult patients (aged 19-80 years) who were enrolled and randomized from July 28, 2020, to March 9, 2023, at 18 hospitals in South Korea. Enrolled patients had at least 1 non-sex-related stroke risk factor (determined using the CHA₂DS₂-VASc score [range, 0-9]) and no documented recurrence of atrial arrhythmia for at least 1 year after catheter ablation for AF. The CHA₂DS₂-VASc score is used as an assessment of stroke risk among patients with AF (calculated using point values for congestive heart failure, hypertension, ≥75 years of age, diabetes, stroke or transient ischemic attack, vascular disease, between 65 and 74 years of age, and sex category). The date of final follow-up was June 4, 2025. Interventions: The patients were randomly assigned in a 1:1 ratio to discontinue oral anticoagulant therapy (n = 417) or continue oral anticoagulant therapy (with direct oral anticoagulants; n = 423). Main Outcomes and Measures: The primary outcome was the first occurrence of a composite of stroke, systemic embolism, and major bleeding at 2 years. Individual components of the primary outcome (such as ischemic stroke and major bleeding) were assessed as secondary outcomes. Results: Of the 840 adults randomized, the mean age was 64 (SD, 8) years, 24.9% were women, the mean CHA₂DS₂-VASc score was 2.1 (SD, 1.0), and 67.6% had paroxysmal AF. At 2 years, the primary outcome occurred in 1 patient (0.3%) in the discontinue oral anticoagulant therapy group vs 8 patients (2.2%) in the continue oral anticoagulant therapy group (absolute difference, -1.9 percentage points [95% CI, -3.5 to -0.3]; P =.02). The 2-year cumulative incidence of ischemic stroke was 0.3% in the discontinue oral anticoagulant therapy group vs 0.8% in the continue oral anticoagulant therapy group (absolute difference, -0.5 percentage points [95% CI, -1.6 to 0.6]). Major bleeding occurred in 0 patients in the discontinue oral anticoagulant therapy group vs 5 patients (1.4%) in the continue oral anticoagulant therapy group (absolute difference, -1.4 percentage points [95% CI, -2.6 to -0.2]). Conclusions and Relevance: Among patients without documented atrial arrhythmia recurrence after catheter ablation for AF, discontinuing oral anticoagulant therapy resulted in a lower risk for the composite outcome of stroke, systemic embolism, and major bleeding vs continuing direct oral anticoagulant therapy.