Safety and long-term outcomes of catheter ablation according to sex in patients with atrial fibrillation: A nationwide cohort study

Background: Catheter ablation is more effective than antiarrhythmic drug therapy alone in patients with atrial fibrillation (AF). However, there are limited data on the outcomes of AF ablation according to sex. The purpose of this study was to evaluate gender differences in the actual outcomes after catheter ablation for atrial fibrillation. Methods: Of 801,710 patients with AF in the Korean National Health Insurance Service database, we identified 9175 patients without valvular heart disease who underwent AF ablation between 2006 and 2015 and assessed 30-day safety and one-year effectiveness outcomes according to sex. Results: Of the 9175 patients who underwent AF ablation, 2206 (24%) were female. Women, compared to men, were older (60.8 ± 10.2 vs. 56.0 ± 10.5 years), had higher CHA₂DS₂-VASc (3.5 ± 1.7 vs. 2.0 ± 1.6), higher HAS-BLED (2.6 ± 1.3 vs. 2.4 ± 1.2), and higher Charlson comorbidity index scores (3.8 ± 2.6 vs. 3.1 ± 2.5) (p < 0.001 for all). Following ablation, there was no significant difference in the risk of 30-day complications, including hemorrhage and tamponade, between women and men. In multivariable analyses, there were no significant differences in all-cause hospitalization (adjusted hazard ratio [HR] 1.05, 95% confidence interval [CI] 0.91–1.22, p = 0.489) and AF rehospitalization (adjusted HR 1.16, 95% CI 0.96–1.40, p = 0.135). Women were less likely to undergo cardioversion (adjusted HR 0.72, 95% CI 0.62–0.84, p < 0.001) but were more likely to be re-hospitalized for heart failure (adjusted HR 1.86, 95% CI 1.11–3.11, p = 0.019). Conclusion: Women who underwent AF ablation did not differ from men in terms of the risk of complications and all-cause hospitalization in this study. The small increased risk in women reported in previous studies may be related to residual confounding, particularly from insufficient control for age and comorbidities.