Smoking and Risk of Atrial Fibrillation Recurrence After Catheter Ablation: A Meta-Analysis and Meta-Regression.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia worldwide. Although catheter ablation is an established rhythm-control strategy, recurrence remains frequent. Smoking is a potentially modifiable risk factor, but its impact on post-ablation AF recurrence remains uncertain. This study evaluated the association between smoking status and AF recurrence following catheter ablation. METHOD: Six databases were searched up to March 2026. Studies including patients with AF undergoing first-time catheter ablation and reporting recurrence outcomes stratified by smoking status were included. Sensitivity, subgroup, and meta-regression analyses were performed. Publication bias was evaluated using Egger's test and trim-and-fill analysis. RESULT: Twenty-two studies comprising 6047 participants were included. Smoking was associated with a significantly increased risk of AF recurrence following catheter ablation (OR 1.42, 95% CI: 1.09-1.85; p = 0.0096), with substantial heterogeneity (I 2 = 65.8%). Sensitivity analysis confirmed the robustness of the findings (OR 1.35, 95% CI: 1.05-1.73). No significant small-study effects were detected (Egger's p = 0.4280), although trim-and-fill analysis attenuated the association to borderline significance. Meta-regression identified body mass index (BMI) as a significant moderator, with a weaker association observed in populations with higher BMI. CONCLUSION: Smoking is associated with a modest but significant increase in the risk of AF recurrence after catheter ablation. Future studies should evaluate the impact of smoking intensity, duration, and cessation on ablation outcomes using patient-level data.