Gender differences in complications following catheter ablation of atrial fibrillation

Aims: Population studies that provide unbiased estimates of gender differences in risk of complications following catheter ablation of atrial fibrillation (AF) are sparse. We sought to evaluate the association of female gender and risk of complications following AF ablation in a nationwide cohort. Methods and results: We identified 35 211 patients (29.5% females) undergoing AF ablations from 2008 to 2017 using national hospitalization data from Australia and New Zealand. The primary outcome was any procedural complication occurring up to 30-days after discharge. Logistic regression was used to adjust for differences in baseline characteristics between sexes. Compared with males, females were older (mean age 64.9 vs. 61.2 years), had higher rates of hypertension (14.0% vs. 11.6%) and haematological disorders (5.3% vs. 3.8%) and experienced a higher rate of procedural complications (6.96% vs. 5.41%) (all P < 0.001). This gender disparity remained significant after adjustment [odds ratio (OR) 1.25 (95% confidence interval 1.14-1.38), P < 0.001] and was driven by an increased risk of vascular injury [OR 1.86 (1.23-2.82), P = 0.003], pericarditis [OR 1.86 (1.16-2.67), P = 0.008], pericardial effusion [OR 1.71 (1.35-2.17), P < 0.001), and bleeding [OR 1.30 (1.15-1.46), P < 0.001]. Notably, the gender difference persisted over time [OR for the most recent period 1.19 (1.003-1.422), P = 0.046] despite a declining complication rate in both men and women. Conclusion: Females undergoing AF ablations experienced a 25% higher risk of procedural complications compared with males, a disparity that has persisted over time despite a falling complication rate. Efforts to reduce this gender disparity should focus on reducing the incidence of pericardial effusion, pericarditis, vascular injury, and bleeding.