Impact of Female Sex on Clinical Presentation and Ablation Outcomes in the CIRCA-DOSE Study

Abstract Objectives This study sought to evaluate sex-specific differences in atrial fibrillation (AF) presentation and catheter ablation outcomes in the prospective, multicenter, randomized CIRCA-DOSE (Cryoballoon vs. Irrigated Radiofrequency Catheter Ablation: Double Short vs. Standard Exposure Duration) study. Background Similar to other cardiovascular conditions, significant sex-specific differences have been observed in the epidemiology, pathophysiology, presentation, and natural history of AF. Unfortunately, there are major gaps in our understanding of the pathophysiological basis for the observed sex-specific differences and their implications on therapy and prognosis. Methods This study examined sex-specific differences in AF presentation, symptom severity and health-related quality of life, symptomatic and asymptomatic arrhythmia recurrence, AF burden, and health care utilization. Results Freedom from any atrial tachyarrhythmia and symptomatic atrial tachyarrhythmia were similar between male (hazard ratio: 1.18; 95% confidence interval: 0.85 to 1.64; p = 0.39) and female patients (hazard ratio: 1.00; 95% confidence interval: 0.62 to 1.59; p = 0.92). Post-ablation, the median AF burden (percentage time in AF) was 0.00% (interquartile range: 0.00% to 0.16%) in male patients and 0.00% (interquartile range: 0.00% to 0.17%) in female patients, with no difference observed between the sexes (p = 0.30). Periprocedural complications occurred twice as frequently in female patients (3.5% vs. 7.0%, p = 0.18). In comparison to male patients, female patients reported a significantly worse symptom score and quality of life at baseline and all follow-up intervals, but they derived similar magnitude of improvement post-ablation. There was no difference between male and female patients with respect to emergency department visits, hospitalization, cardioversion, or repeat ablation. Conclusions When compared with male patients, female patients have significantly worse symptom scores and quality of life at baseline. Despite this, female patients with symptomatic paroxysmal AF derive similar benefit in freedom from recurrent arrhythmia and similar improvements in quality of life following AF ablation. (Cryoballoon vs. Irrigated Radiofrequency Catheter Ablation: Double Short vs. Standard Exposure Duration [CIRCA-DOSE]; NCT01913522 )