Some studies have shown an association between epicardial fat thickness (EFT) and atrial fibrillation development or its recurrence after ablation.

The objective of this study was to evaluate whether EFT could predict the outcome of patients undergoing a first pulmonary vein isolation (PVI) procedure using second-generation cryoballoon catheter for paroxysmal atrial fibrillation (PAF).

Clinical and imaging data were retrospectively collected in patients who underwent a first PVI procedure for PAF using second-generation cryoballoon catheter, from February 2012 to October 2016, at Rouen university hospital. EFT was measured using either cardiac computed tomography (CT) or cardiac magnetic resonance imaging (MRI), performed to evaluate the left atrium anatomy before the ablation procedure. A mean value of EFT was calculated for each patient using several measurements performed along the right ventricle free-wall in four-chamber view. Redo atrial fibrillation ablation procedure was the primary endpoint of the study.

Among the 245 patients eligible for the study, EFT could be analyzed in 191 patients [MRI: n=165 (86.4%); CT: n=26 (13.6%)]. Twenty-seven patients (14.1%) underwent a redo procedure, which was performed 9.9±9.5 months after the first ablation. In these patients, EFT was significantly greater than in the other patients using univariate analysis. It remained a significant predictive factor of redo procedure in multivariate analysis (Table 1). The ROC curve exploring the relation between EFT and the performance of redo procedure reported an area under the curve equal to 0.79, and a best cut off value of 4.7mm with sensitivity of 76% and a specificity of 74%.

EFT seems to be an independent and strong predictive factor of redo ablation procedure following PVI using cryoballoon catheter for PAF. Whether this parameter could help to better define the PAF ablation, strategy remains to be determined.