PO-03-095 SEX-RELATED DIFFERENCES IN ATRIAL SUBSTRATE IN PATIENTS UNDERGOING PULMONARY VEIN ISOLATION; A PROSPECTIVE, MULTICENTER STUDY

Abstract

Sex-related differences have been reported among patients undergoing pulmonary vein isolation (PVI). Atrial substrate plays a major role in the outcomes after ablation but sex-related differences in atrial substrate have never been described in detail. We sought to analyze sex-related differences in atrial remodeling (spontaneous low-voltage zones (LVZ)) and their clinical relevance after PVI. We conducted a prospective multicenter study, including consecutive patients undergoing first PVI-only AF ablation. LVZs were analyzed on high-density electroanatomical maps collected with multipolar catheter, prior to PVI. 262 patients (61±11 years, 31% females, 50% persistent AF) were followed for 28 months. In women, LVZs were larger (10% vs. 4% of LA surface (p < 0.001)) and more women had high-burden (>15%) LVZs (24% vs. 8% (p < 0.001)). In spite of women having more advanced atrial remodeling, AF recurrence-free survival was similar between men and women (Log-Rank p=0.2). The presence of >5% LVZ was significantly associated with recurrence in men (HR:3.0, p<0.001) but not in women (HR:1.9, p=0.07). In women, only >15% LVZ was associated with recurrence (HR: 2.7, p=0.02). Women have more widespread LVZ in all LA regions. Despite more extensive atrial remodeling, the efficacy of first PVI-only ablation is similar in men and women, and LVZs become prognostic in women only at high burden (>15%). LVZs seem to have a different prognostic role in men and women.