Impact of Obesity Phenotypes on Efficacy and Safety of Catheter Ablation for Patients with Paroxysmal Atrial Fibrillation.

Background: Obesity is a major risk factor for atrial fibrillation (AF). Individuals with obesity can be further classified into metabolically unhealthy obesity (MUO) or healthy obesity (MHO) groups based on the metabolic health subtype. The influence of these phenotypes and overweight status on AF ablation outcomes remains unclear. Objective: This study aimed to examine the recurrence of paroxysmal AF (PAF) after ablation in patients across distinct obesity phenotypes. Methods: From January 2019 to November 2023, 599 patients with drug-refractory PAF undergoing a first ablation were retrospectively analyzed. Based on the World Health Organization-defined body mass index thresholds for Asians regarding overweight (23-25 kg/m2) and obesity (> 25 kg/m2), the participants were categorized into normal-weight, metabolically healthy overweight (MHOW), metabolically unhealthy overweight (MUOW), MHO, or MUO groups. Metabolic health required the absence of hypertension, diabetes, and dyslipidemia. Pulmonary vein isolation was achieved using either a force-sensing catheter or cryoablation. Results: The mean age of the patients was 60.7 ± 11.7 years, and 64.1% were men. Compared with the normal-weight patients, AF recurrence was higher in the MUOW (19.8%), MHO (18.0%), and MUO (14.9%) groups after an average follow-up of 534 days, with respective hazard ratios (HRs) of 3.240 (p = 0.003), 2.973 (p = 0.013), and 2.182 (p = 0.033) after adjusting for chronic kidney disease. MHOW (14.9%; HR 2.593, p = 0.053) showed a non-significant trend toward a higher risk. Complete pulmonary vein isolation was achieved in all patients. Conclusions: Overweight and obesity, regardless of metabolic status, were associated with a significantly higher risk of AF recurrence after ablation compared to normal-weight, underscoring the importance of weight management in PAF.