Background: Studies have identified significant sex-based differences and disparities in the clinical presentation and treatment of atrial fibrillation (AF). Studies have shown women are less likely to be referred for catheter ablation, are older at the time of ablation, and are more likely to have recurrence after ablation. However, in most studies investigating AF ablation outcomes, the female cohorts were relatively small. The impact of gender on the outcome and safety of ablation procedures is still unclear. Objective: To investigate sex-based differences in outcomes and complications after AF catheter ablation, with a significant size female cohort Method: In this retrospective study, patients undergoing AF ablation from January 1, 2014, to March 31, 2021, were included. We investigated clinical characteristics, duration and progression of AF, number of EP appointments from diagnosis to ablation, procedural data, and procedure complications. Results: Total 1346 patients underwent first catheter ablation for AF during this period, including 896 (66.5%) male and 450 (33.4%) female patients. Female patients were older at the time of ablation (66.2y vs 62.4y; p<0.001). Women had higher CHA 2DS 2-VASc scores (3 vs 2; p<0.001) than men, expectedly, as the female sex warrants an additional point. 25.3% female patients had PersAF at the time of diagnosis vs 35.3% male patients (p<0.001). At the time of ablation, 31.8% female patients had PersAF as compared to 43.1% male patients (p<0.001), indicating progression of PAF to PersAF in both genders. Women tried more AADs than men before ablation (1.13 vs 0.98; p=0.002). Male and female patients had no statistically significant difference in (a) arrhythmia recurrence at 1-y post ablation (27.7% vs 30%; p=0.38) or (b) procedural complication rate (1.8% vs 3.1%; p=0.56). Conclusion: Female patients were older and had higher CHA 2DS 2-VASc scores compared to males at the time of AF ablation. Women tried more AADs than men prior to ablation. 1-y arrhythmia recurrence rates and procedural complications were similar in both genders. No sex- based differences were observed in safety and efficacy of ablation.

Background: Catheter ablation for atrial fibrillation (AF) is a common therapeutic strategy for patients with either paroxysmal or persistent AF, but long-term ablation success rates are imperfect. Maintenance of sinus rhythm immediately prior to ablation with anti-arrhythmic drug (AAD) therapy has been associated with improved outcomes in patients undergoing ablation. Amiodarone has superior efficacy relative to other AADs. Whether failure of amiodarone to maintain sinus rhythm prior to ablation for either paroxysmal or persistent AF is associated with poor outcomes is unknown. Methods: A total of 307 patients who received amiodarone in a one-year window before undergoing catheter ablation for AF were included. Patients were divided into amiodarone success (n=183) and amiodarone failure (n=124) groups based on the response to pre-ablation amiodarone treatment. Analysis of procedural outcomes as a function of response to amiodarone therapy was performed. Patients were followed for at least 12 months post-ablation to assess outcomes (adverse events and arrhythmia recurrence). Procedural success was defined by the absence of documented arrhythmia (>30s) without any anti-arrhythmic agents beyond a 90d blanking period. Results: Following ablation for either paroxysmal or persistent AF, freedom from any recurrent atrial arrhythmia at 1y was 57.7% for the entire cohort. One-year freedom from recurrent arrhythmia in the amiodarone success group was comparable to that in the amiodarone failure group (55.7% vs 60.5%; p=0.54). Success rates following ablation did not vary by the response to amiodarone when analyzed for paroxysmal or persistent AF subgroups. Conclusion: Failure to restore and maintain sinus rhythm with amiodarone prior to ablation for either paroxysmal or persistent AF is not a predictor of ablation procedural failure. Amiodarone failure alone should not deter practitioners from considering ablation therapy for patients with AF.