ABC | Volume 110, Nº5, May 2018

Original Article Paroxysmal Atrial Fibrillation in Females: Understanding Gender Differences Gabriel Odozynski, 1,2 Alexander Romeno Janner Dal Forno, 2 Andrei Lewandowski, 2 Hélcio Garcia Nascimento, 2 André d'Avila 2 Universidade Federal de Santa Catarina, 1 Florianópolis, SC – Brazil Serviço de Arritmia e Marcapasso - Hospital SOS Cardio, 2 Florianópolis, SC – Brazil Mailing Address: Gabriel Odozynski • Rodovia SC 401 - Hospital SOS Cardio. Postal Code 88030-000, Itacorubi, Florianópolis, SC – Brazil E-mail: cardio.gabriel@gmail.com Manuscript received August 28, 2017, revised manuscript November 09, 2017, accepted November 22, 2017 DOI: 10.5935/abc.20180069 Abstract Background: The catheter ablation of atrial fibrillation (AF) is performed less frequently in women. In addition, there is divergent information in the literature regarding the effectiveness and safety for the ablative procedure to females. Objectives: The objective of this study was to compare the clinical characteristics and outcomes in men and women undergoing paroxysmal atrial fibrillation (PAF) ablation. Methods: Cohort study of patients undergoing first-ever PAF catheter ablation procedure refractory to antiarrhythmic drugs. The information was taken from patients’ records by means of a digital collection instrument and indexed to an online database (Syscardio®). Clinical characteristics and procedures were compared between each gender (M x F), adopting a level of statistical significance of 5%. The primary endpoint associated with efficacy was freedom from atrial arrhythmia over the follow-up time. Results: 225 patients were included in the study, 64 (29%) women and 161 (71%) men. Women presented more symptoms due to AF according to the CCS-SAF score (1.8 ± 0.8M x 2.3 ± 0.8F p = 0.02) and higher CHADS2 score compared to men (0.9 ± 0.8M x 1.2 ± 1F). Post-ablation recurrence occurred in 20% of the patients, with no difference based on gender (21% M x 20% F p = 0.52). The rate of complications was less than 3% for both groups (p = 0.98). Conclusion: Women undergoing the first-ever PAF catheter ablation procedure present similar complication rate and clinical outcome compared to men. These findings suggest that the current underutilization of AF catheter ablation in women may represent a discrepancy in care. (Arq Bras Cardiol. 2018; 110(5):449-454) Keywords: Arrhythmias,Cardiac; Atrial Fibrillation; Catheter Ablation; Cardiac Electrophysiology; Gender. Introduction Although age-adjusted prevalence of atrial fibrillation (AF) is relatively higher in men than in women, the absolute number of arrhythmia patients between genders is similar, with most cases occurring in patients between 65 and 85 years of age, a period in which, proportionately, more women are alive. 1 Population studies show lower indication and execution rates of ablative treatment for AF in women with atrial fibrillation compared to men. 2-5 However, it is not clear whether this represents a discrepancy in assistance or a real difference. Based on the assumption that higher rates of complications and recurrence occur in women compared to men, the underutilization of AF ablation in women in this case, could be understood as an appropriate difference and not a direct lack of assistance. Previous studies evaluating differences between genders regarding safety and efficacy AF catheter ablation have conflicting results, and Brazilian literature on the topic is scarce. 6-13 In this study, we evaluated clinical characteristics and outcomes of a current Brazilian women cohort undergoing ablation of AF per catheter compared to results obtained in men. Methods Study design and participants Cohort study of patients undergoing the first catheter ablation procedure for paroxysmal atrial fibrillation (FAP) refractory to antiarrhythmic drugs with minimum follow-up time per patient of 12 months. The study was conducted between 2013 and 2015 in a single center. Information was collected from patients' records by means of a digital collect instrument and indexed to an online database (Syscardio®). Clinical characteristics and procedures were compared between genders (M x W). Primary endpoint associated with efficacy was atrial arrhythmia absence lasting > 30 seconds during the follow-up period after first and only ablation procedure. 449