Background
Obesity is a known risk factor for atrial fibrillation (AF), contributing to increased incidence, greater symptom burden, and technical challenges during catheter-based ablation procedures. The presence of excess adipose tissue is associated with atrial remodeling, inflammation, and pericardial fat accumulation, which may compromise procedural efficacy and increase complication risk of thermal ablation. Pulsed field ablation (PFA), a novel, non-thermal ablation technology has shown promise for improving safety and efficiency in AF ablation. However, its utility in obese patients has not been systematically evaluated.
Aims
To assess safety and efficacy of 3D electroanatomical mapping-guided PFA for pulmonary vein isolation (PVI) in obese versus non-obese patients with paroxysmal or persistent AF.
Methods In this prospective study, we analyzed a total of 648 consecutive patients who underwent pulsed field ablation (PFA) for atrial fibrillation (AF) at a single high volume center between 2021 and 2024. All procedures were guided by high-resolution 3D-electroanatomical mapping and conducted in deep sedation. PFA was performed using a commercially available system comprising a steerable device sheath and a catheter capable of assuming both a flower and a basket configuration. Patients were stratified into five groups according to body mass index (BMI): normal weight (18.5–24.9 kg/m²), overweight (25.0–29.9 kg/m²), class I obesity (30.0–34.9 kg/m²), class II obesity (35.0–39.9 kg/m²), and class III obesity (≥40.0 kg/m²). Baseline demographics, procedural metrics, complication rates, and arrhythmia recurrence were assessed.
Results
Baseline characteristics were comparable between BMI subgroups except for more frequent hypertension (79% vs. 53%, p=0.027). Acute PVI was achieved in all patients (100%) irrespective of BMI group. All procedures were performed in deep sedation without any patient being converted to general anaesthesia. No major periprocedural complications occurred in any group. Minor complications, including vascular access site issues, were infrequent and comparable (5.9% in obese vs. 5.6% in non-obese, p=0.97). There were no significant differences in total procedure time or fluoroscopy duration between BMI groups. At 12-month follow-up, arrhythmia recurrence was observed in 9.3% of patients with normal BMI. Recurrence rates were higher in patients with obesity: 23.7% in overweighed patients, 29.1% in class I obesity, 24.6% in class II obesity, and 28.1% in class III obesity.
Conclusion
3D-mapping guided PFA is a safe and effective strategy for AF ablation in obese patients, with procedural efficiency, safety, and mid-term efficacy comparable to those observed in non-obese individuals. Our findings support the integration of 3D-mapping guided PFA into routine practice for a broader spectrum of patients, including those with pronounced obesity.
