Sex differences in patients undergoing pulmonary vein isolation with high power short duration ablation and CLOSE protocol

Abstract Introduction Sex differences in patients undergoing pulmonary vein isolation (PVI) for atrial fibrillation (AF) are well documented, with women typically presenting at an older age, having more comorbidities, and experiencing delayed referral. Women also exhibit higher rates of major complications and AF recurrence compared to men. Recent procedural advancements, such as high-power short-duration (HPSD) ablation and the Close-Protocol, aim to reduce recurrence risk post-PVI and reduce complication rates. Little is known about the safety and effectiveness of these new procedural strategies in women. Purpose Aim of this study was to compare safety and effectiveness of PVIs performed with RF-Energy (RF) using high power short duration and the CLOSE protocol in women versus men. Methods This prospective multicenter study included patients who underwent their first PVI at DHZC consecutively. All procedures employed HPSD ablation (50W, max temperature 43°C, max duration 25 seconds) and the Close-Protocol (interlesion distance <6mm, AI target >550 anterior wall, >400 posterior wall). Follow-up excluded early recurrences (within 3 months). Results A total of 241 patients were analyzed, with 96 (39.8%) female. The mean age was 67.8 ± 10.8 years, and 114 (47.3%) had paroxysmal AF. Baseline characteristica are shown in Figure 1. Female patients were older (70.3 ± 9.7 vs. 66.2 ± 11.2 years, p<0.004) and had lower rates of CAD (10.4% vs. 44.1%, p<0.001), diabetes type 2 (9.4% vs. 20.0%, p=0.027), and HFrEF (3.1% vs. 17.5%, p<0.001) compared to men. Women more frequently showed low-voltage areas in the septal region (24.4% vs. 12.2%, p=0.019), with no significant differences in other atrial regions. There were no significant differences in major procedural complications between men and women. Follow-up data (>3 months) was available for 218 patients (mean duration 28.2 ± 12.7 months). AF recurrence after the 3-month-blanking period occurred in 36.7% (n=80) of patients, with no significant gender differences (33.7% in women vs. 38.3% in men, p=0.447). a Kaplan-meier curve with arrhythmia-free survival is shown in figure 1. Arrhythmia-related symptoms were reported by 34.3% (74/216), with no gender differences. Risk factors for recurrence in women included BMI (p=0.007), mitral regurgitation (p=0.031), LA volume (p=0.023), and the presence of low-voltage areas overall (p=0.047) and in the septal region (p=0.047). In men, recurrence risk factors included low-voltage areas on the posterior wall (p=0.004) and non-isolation at the first encircling (p=0.021). Conclusion This study suggests that while the Close-Protocol and HPSD ablation show similar recurrence rates in men and women, female patients have distinct risk factors for recurrence and there are no differences in complication rates. Targeted strategies addressing gender-specific risk profiles may further improve outcomes in AF ablation.