Poor Rhythm Outcome of Catheter Ablation for Early-Onset Atrial Fibrillation in Women - Mechanistic Insight

BACKGROUND: Catheter ablation is a good treatment option for atrial fibrillation (AF) in young symptomatic patients. However, there is little information on the efficacy of catheter ablation of early-onset AF between sexes. Methods and Results: This study included 1,060 patients under the age 60 years old (837 men, 49.8±7.7 years old, 70.8% paroxysmal AF) who underwent catheter ablation for AF. Sex differences in clinical presentation and ablation outcomes were compared with and without propensity score-matching. During 24.5±18.9 months of follow-up, women showed significantly higher clinical recurrence of AF than men (log-rank, P=0.002). Female sex was independently associated with post-ablation clinical recurrence of AF (adjusted hazard ratio (HR) 2.58 [1.06-6.30], P=0.037). Women had a higher proportion of left ventricular diastolic dysfunction (E/Em, P<0.001), higher prevalence of heart failure (P=0.017), greater left atrial (LA) volume index (P=0.001), lower LA endocardial voltage (P<0.001), and higher parasympathetic nervous activity (root-mean square of differences, P