Abstract
Background: Epicardial adipose tissue (EAT) may contribute to the pathogenesis of atrial fibrillation (AF). The attenuation of EAT assessed by means of computed tomography (CT) may reflect the severity of local tissue inflammation. This study aimed to systematically analyze the relationship between the attenuation of EAT surrounding the left atrium (LA-EAT) and AF recurrence after catheter ablation (CA). Methods: Five databases were searched up to April 10, 2025. Original studies involving adult patients with paroxysmal or persistent AF undergoing CA were included if they provided quantitative measurements of LA-EAT attenuation on cardiac CT before ablation. Results: A total of seven retrospective observational studies with 2440 patients were included in the analysis. The percentage of male participants ranged from 60.9% to 73.0%, and the mean or median age of patients varied from 57.5 to 68.2 years. The mean body mass index across studies ranged from 24.0 to 32.4 kg/m(2). A pooled analysis of all included trials demonstrated that the mean LA-EAT attenuation in the AF recurrence group was -78.97 ± 15.34 HU, which was less negative compared to the non-recurrence group (-81.37 ± 15.46 HU; mean difference [MD] = 2.22; 95% confidence interval [CI]: 0.84 to 3.61; p = 0.002). Conclusions: LA-EAT attenuation is significantly more positive in patients experiencing AF recurrence compared to those without recurrence following CA procedures.