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 if catheter ablation of AF can lead to an additional stroke protection benefit in these patients.

Objective: Investigating a possible stroke protective benefit by catheter ablation in AF.

Methods: Systematic review of contemporary randomized controlled trials comparing catheter ablation vs. medical treatment. We searched MEDLINE, EMBASE and CENTRAL in February 2025, pooled data through risk ratios (RRs) with 95% confidence intervals (CIs), and calculated the Number Needed to Treat (NNT). Quality of evidence was assessed using the GRADE framework. Sub-group and sensitivity analyses were performed for presence/absence of heart failure, CHA₂DS₂VASc≥2 or <2, paroxysmal/persistent AF, early ablation, studies allowing discontinuation of oral anticoagulation post-ablation, higher/lower quality, published ≤5 vs >5 years ago, and ≥12 vs < 12 months follow-up.

Results: We identified 18 eligible randomized controlled trials, including 5877 patients. Catheter ablation was associated with a significant reduction in stroke (RR: 0.63, 95%CI 0.45 to 0.87, P=0.006; Quality of evidence: Moderate), with low heterogeneity observed (I²=0), and a NNT of 78.7 patients to prevent one stroke. Sub-group and sensitivity analyses yielded similar estimates with 30 to 40% relative risk reduction for all sub-analyses, except for trials with less than one year of follow-up.

Conclusion: Pooling of high-quality randomized controlled trial 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.