Ablation of atrial fibrillation and risk of stroke: A meta-analysis.

Background: Despite treatment with anticoagulants, patients with atrial fibrillation (AF) remain exposed to a relevant residual risk of stroke. It remains to be proven whether catheter ablation of AF can lead to an additional stroke protection benefit in these patients.

Objective: This study aimed to investigate a possible stroke protective benefit by catheter ablation in AF.

Methods: This is a systematic review of contemporary randomized controlled trials (RCTs) comparing catheter ablation with medical treatment. We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials in February 2025, pooled data through relative risks (RRs) with 95% confidence intervals, and calculated the number needed to treat. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation framework. Subgroup and sensitivity analyses were performed for presence/absence of heart failure, CHADS-VASc of ≥2 or <2, paroxysmal/persistent AF, early ablation, studies allowing discontinuation of oral anticoagulation after ablation, higher/lower quality, published ≤5 vs >5 years ago, and ≥12- vs <12-month follow-up.

Results: We identified 18 eligible RCTs, including 5877 patients. Catheter ablation was associated with a significant reduction in stroke (RR 0.63, 95% confidence interval 0.45-0.87, P = .006; quality of evidence, moderate), low heterogeneity observed (I = 0), and a number needed to treat of 78.7 patients to prevent 1 stroke. Subgroup and sensitivity analyses yielded similar estimates with 30%-40% RR reduction for all subanalyses, except for trials with less than 1 year of follow-up.

Conclusion: Pooling of high-quality RCT data suggests that catheter ablation may lead to significant stroke reduction. A confirmatory trial will be required to provide a conclusive answer to this matter.