Epicardial adipose tissue volume assessed by cardiac CT as a predictor of atrial fibrillation recurrence following catheter ablation

Introduction: In patients with atrial fibrillation (AF), up to one third have recurrence after a first catheter ablation (CA). Epicardial adipose tissue (EAT) has been considered to be closely related to AF, with a potential role in its recurrence. We aimed to evaluate the association between the volume of EAT measured by cardiac computed tomography (CT) and AF recurrence after CA. Methods: Consecutive AF patients underwent a standardized cardiac CT protocol for quantification of EAT, thoracic adipose volume (TAV) and left atrium (LA) volume before CA. An appropriate cut -off of EAT was determined and risk recurrence was estimated. Results: 305 patients (63.6 % male, mean age 57.5 years, 28.2 % persistent AF) were followed for 24 months; 23 % had AF recurrence at 2 -year mark, which was associated with higher EAT ( p = 0.037) and LAV ( p < 0.001). Persistent AF was associated with higher EAT volumes ( p = 0.010), TAV ( p = 0.003) and LA volumes (p < 0.001). EAT was predictive of AF recurrence ( p = 0.044). After determining a cut -off of 92 cm( 3) , survival analysis revealed that EAT volumes > 92 cm( 3) showed higher recurrence rates at earlier time points after the index ablation procedure ( p = 0.006), with a HR of 1.95 ( p = 0.008) of AF recurrence at 2 -year. After multivariate adjustment, EAT > 92 cm( 3) remained predictive of AF recurrence ( p = 0.028). Conclusion: The volume of EAT measured by cardiac CT can predict recurrence of AF after ablation, with a volume above 92 cm( 3) yielding almost twice the risk of arrhythmia recurrence in the first two years following CA. Higher EAT and TAV are also associated with persistent AF.