Asthma is associated with higher recurrence rates of atrial fibrillation after catheter ablation.

Background: Asthma is a known risk factor for atrial fibrillation (AF), the most common sustained arrhythmia. Whereas radiofrequency catheter ablation is effective in treating AF, the impact of asthma and its severity on ablation outcomes has not been previously explored.

Objective: The purpose of this study was to evaluate the impact of asthma and its severity on AF recurrence after ablation.

Methods: In this single-center retrospective case-control study, 63 case patients with AF and asthma who underwent ablation were matched with 126 controls with AF but without asthma who underwent ablation. Case patients were also compared with a nonablated cohort of patients with asthma. AF recurrence was compared between groups. Univariate and multivariate analyses were conducted to determine associations with recurrence.

Results: Compared with controls who underwent ablation, patients with asthma, particularly those with severe asthma, had a higher likelihood of AF recurrence after catheter ablation (odds ratio, 3.76 [P = .047] and 5.06 [P = .041], respectively). However, case patients were not more likely to experience adverse outcomes. Multivariate analysis revealed that persistent AF and use of a beta blocker were associated with recurrence. Patients with moderate or severe persistent asthma were more likely than patients with intermittent or mild persistent asthma to have left atrial enlargement (odds ratio, 2.53; P = .009).

Conclusion: Patients with AF and asthma, particularly those with severe asthma, were more likely than patients with AF but without asthma to have AF recurrence after ablation. Patients with AF and severe asthma were also more likely to have severe left atrial enlargement, a known predictor of recurrence after ablation.