Is the ALONE‑AF trial a real study, and does it show that stopping oral anticoagulation is safe in adults (19‑80 years) with non‑valvular atrial fibrillation who are arrhythmia‑free ≥12 months after first catheter ablation and have CHA₂DS₂‑VASc ≥1 (men) or ≥2 (women)?

ALONE-AF Trial: Real Study with Groundbreaking Results on Stopping Anticoagulation Post-Ablation

Yes, the ALONE-AF trial is a real, recently published randomized clinical trial in JAMA (2025) that demonstrated stopping oral anticoagulation is SUPERIOR to continuing it in carefully selected patients who remain arrhythmia-free ≥12 months after successful AF catheter ablation. 1

Key Trial Design and Population

The ALONE-AF trial was a prospective, multicenter, open-label randomized clinical trial conducted at 18 hospitals in South Korea, enrolling 840 adults aged 19-80 years from July 2020 to March 2023. 1

Specific inclusion criteria:

• Non-valvular atrial fibrillation with CHA₂DS₂-VASc ≥1 (men) or ≥2 (women) 1
• No documented atrial arrhythmia recurrence for ≥12 months post-ablation 1
• Mean age 64 years, 24.9% women, mean CHA₂DS₂-VASc score 2.1 1
• 67.6% had paroxysmal AF 1

Patients were randomized 1:1 to either discontinue oral anticoagulation (n=417) or continue direct oral anticoagulants (n=423), with 2-year follow-up. 1

Primary Results: Stopping Anticoagulation Was Superior

The primary composite outcome (stroke, systemic embolism, or major bleeding) occurred in only 0.3% of patients who stopped anticoagulation versus 2.2% who continued it (absolute difference -1.9 percentage points, P=0.02). 1

Individual outcome breakdown:

• Ischemic stroke: 0.3% (stopped) vs 0.8% (continued) 1
• Major bleeding: 0% (stopped) vs 1.4% (continued) - absolute difference -1.4 percentage points 1
• Systemic embolism: Included in composite but rare in both groups 1

Critical Context: This Contradicts Current Guidelines

This trial directly challenges established guideline recommendations that mandate lifelong anticoagulation based solely on CHA₂DS₂-VASc score, regardless of rhythm control success. Current ACC/AHA guidelines recommend oral anticoagulation for CHA₂DS₂-VASc ≥2 (men) or ≥3 (women) independent of whether patients maintain sinus rhythm. 2, 3, 4

The European Society of Cardiology explicitly states that anticoagulation should continue regardless of cardioversion success or rhythm control, as stroke risk is determined by CHA₂DS₂-VASc score, not current rhythm. 5 The guidelines emphasize that discontinuing anticoagulation because patients converted to sinus rhythm is a "critical error." 5

Why This Trial Matters Clinically

ALONE-AF is the FIRST randomized trial to address this therapeutic question - all prior recommendations were based on observational data and consensus opinion. 6, 1

Key clinical implications:

• Successful ablation with documented arrhythmia-free status ≥12 months may fundamentally alter thromboembolic risk 1
• The bleeding risk from continued anticoagulation (1.4%) exceeded the stroke risk from stopping (0.3%) in this population 1
• This represents a paradigm shift for post-ablation anticoagulation management 1

Critical Caveats and Limitations

This approach requires RIGOROUS patient selection:

• Documented absence of atrial arrhythmia for ≥12 months (likely requiring continuous monitoring or frequent rhythm assessments) 1
• Patients must be willing and able to undergo close surveillance 6
• Mean CHA₂DS₂-VASc was only 2.1 - results may not apply to very high-risk patients 1

Important limitations:

• Conducted only in South Korea - generalizability to other populations uncertain 1
• Relatively short 2-year follow-up - longer-term outcomes unknown 1
• Method of arrhythmia surveillance not fully detailed in available data 1
• Excludes patients with documented arrhythmia recurrence 1

How This Conflicts With Standard Practice

Current guidelines from ACC/AHA and ESC do NOT support stopping anticoagulation post-ablation in patients with elevated CHA₂DS₂-VASc scores. 2, 3, 5, 4 The guidelines emphasize that:

• Anticoagulation decisions are based on stroke risk factors, not rhythm status 3, 4
• Even patients in sinus rhythm require anticoagulation if CHA₂DS₂-VASc ≥2 (men) or ≥3 (women) 3, 4
• Rhythm control does not eliminate stroke risk 5

Until guidelines are updated to incorporate ALONE-AF results, stopping anticoagulation post-ablation remains technically off-guideline, though now supported by Level 1 evidence. 1