ALONE-AF Studie

Kim D et al.: Long-Term Anticoagulation Discontinuation After Catheter Ablation for Atrial Fibrillation. The ALONE-AF Randomized Clinical Trial. JAMA 31.8.2025. doi:10.1001/jama.2025.14679

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.

Trial Registration ClinicalTrials.gov Identifier: NCT04432220

OCEAN Studie

Verma A et al.: Antithrombotic Therapy after Successful Catheter Ablation for Atrial Fibrillation. NEJM 8.11.2025. DOI: 10.1056/NEJMoa2509688

BACKGROUND
Whether successful catheter ablation for atrial fibrillation eliminates the need for
long-term oral anticoagulant therapy is unknown.
METHODS
We conducted an international, open-label, randomized, blinded-outcome-assess-
ment trial involving 1284 patients who had undergone successful catheter ablation
for atrial fibrillation at least 1 year earlier and had a CHA2DS2-VASc score (scores
range from 0 to 9, with higher scores indicating a higher risk of stroke) of 1 or
more (or ≥2 for women or for patients in whom vascular disease was a risk factor).
Patients were randomly assigned to receive either aspirin (at a dose of 70 to 120
mg daily, depending on availability in the local jurisdiction) or rivaroxaban (at a
dose of 15 mg) and followed for 3 years. Magnetic resonance imaging (MRI) of
the head was performed after enrollment and at 3 years. The primary outcome was
a composite of stroke, systemic embolism, or new covert embolic stroke (defined
by ≥1 new infarct measuring ≥15 mm on MRI) at 3 years.
RESULTS
A total of 641 patients were assigned to the rivaroxaban group and 643 to the aspirin
group. A primary-outcome event occurred in 5 patients (0.31 events per 100 patient-
years) in the rivaroxaban group and in 9 patients (0.66 events per 100 patient-years) in
the aspirin group (relative risk, 0.56; 95% confidence interval [CI], 0.19 to 1.65; abso-
lute risk difference at 3 years, −0.6 percentage points; 95% CI, −1.8 to 0.5; P=0.28).
New cerebral infarcts measuring less than 15 mm occurred in 22 of 568 patients
(3.9%) in the rivaroxaban group and in 26 of 590 patients (4.4%) in the aspirin group
(relative risk, 0.89; 95% CI, 0.51 to 1.55). Fatal or major bleeding (the composite
primary safety outcome) had occurred in 10 patients (1.6%) with rivaroxaban and
in 4 patients (0.6%) with aspirin (hazard ratio, 2.51; 95% CI, 0.79 to 7.95) at 3 years.
CONCLUSIONS
Among patients who had had successful catheter ablation for atrial fibrillation at
least 1 year earlier and had risk factors for stroke, treatment with rivaroxaban did
not result in a significantly lower incidence of a composite of stroke, systemic
embolism, or new covert embolic stroke than treatment with aspirin. (Funded by
Bayer and others; OCEAN ClinicalTrials.gov number, NCT02168829.)