Impact of sex on procedural characteristics, safety and clinical outcomes of pulsed-field ablation for pulmonary vein isolation

Previous studies assessing the impact of patient sex on clinical outcomes using conventional thermal ablation techniques, such as radiofrequency or cryoablation, for the treatment of atrial fibrillation (AF) have yielded mixed results. Pulsed-field ablation (PFA) is a novel, innovative AF ablation modality that offers selective myocardial tissue ablation. Little is known regarding the impact of sex on patients undergoing AF ablation using PFA.

We aim to compare the procedural characteristics, safety, and clinical outcomes of PFA in women and men undergoing a first AF ablation.

This prospective study included consecutive patients undergoing PFA for the treatment of paroxysmal or persistent AF. Follow-up was performed at 3, 6 and 12 months. To estimate the impact of sex on clinical outcomes a 1:1 propensity-score-matched cohort (matched for age, BMI, left atrial volume index and history of hypertension, stroke, coronary artery disease, diabetes, and heart failure) was performed.

Of 425 patients undergoing AF ablation using PFA, 134 patients [32%]) were female. Female patients, as compared with male patients, were significantly older ((median [IQR] age, 70 [62, 75] years vs 65 [58, 72] years; p< .001), had more paroxysmal AF (61% [82 of 134] vs 45% [131 of 291]; p = .002) and had less often coronary disease (4% [6 of 134] vs 14% [40 of 291]; p= .029). Pulmonary vein isolation (PVI) was achieved in all patients. Additional ablation lesions beyond PVI were performed in 31% of female (41 of 134) and 33% of male (96 of 291; p= .70) patients. Median procedure time, LA dwell time and fluoroscopic times were similar in female and male patients. Overall, 2 (0.7%) complications occurred in men and 2 (1.5%; p= .371) in female patients. After propensity score matching (133 women to 133 men) the 1-year recurrence rates for any atrial arrhythmias were 23% (n=30) for females and 11% (n=15) for males (log-rank test; p=.004, Figure 1). Female Sex had an odds ratio of 2.29 for the occurrence of any atrial arrhythmia during long-term-follow-up.

Results of this cohort study suggest that there are important sex differences after PFA for treatment of AF. A better understanding of AF-causal sex-specific mechanisms and refinements in PFA technologies improve success rates in women.Figure 1