A New Paradigm for Atrial Fibrillation Ablation in Obesity Focusing on Substrate Remodeling and Patient-Centered Outcomes

The obesity and atrial fibrillation (AF) epidemics are inextricably linked and continue to increase worldwide, posing significant global health burdens. Epidemiological evidence has revealed that obesity is a powerful, independent, and modifiable risk factor for AF. Obesity directly creates a proarrhythmic substrate through a triad of synergistic pathways: chronic hemodynamic overload that induces left atrial enlargement, local paracrine and inflammatory effects of dysfunctional epicardial adipose tissue (EAT), and systemic inflammation and oxidative stress, which collectively promote atrial fibrosis and electrical remodeling. Catheter ablation remains a cornerstone of rhythm control; however, the efficacy of this procedure is often compromised in patients with obesity, creating a “high-recurrence–high-benefit” paradox in which this patient group achieves the greatest improvements in quality of life despite higher rates of arrhythmia recurrence. Recent large-scale data have further refined this paradox, identifying a distinct “efficacy cliff” among patients categorized as severely obese (body mass index ≥35 kg/m2). Furthermore, emerging concepts are reshaping therapeutic strategies. Novel technologies, such as pulsed field ablation, with an enhanced safety profile, can mitigate the “insulation effect” of EAT; however, these concepts cannot fully overcome this effect without complementary strategic adjustments. Concurrently, recent evidence has suggested that ablation may act as a “biological substrate modification” by reducing the volume of local EAT. These findings support a paradigm shift in therapeutic strategy, moving beyond the singular endpoint of arrhythmia elimination toward a comprehensive approach that applies substrate modification guided by dynamic, spatiotemporally discrete mapping, with the primary endpoints of success shifting to dual endpoints encompassing a reduction in AF burden and an improvement in the quality of life of patients. Overall, this review aimed to discuss the pathophysiological nexus between obesity and AF, critically evaluate the challenges and technological advancements in catheter ablation for this population, and propose an integrated management pathway centered on substrate reversal and quality of life.