Objective: Epicardial adipose tissue (EAT) is a metabolically active tissue and increased thickness is correlated with various cardiovascular diseases. There are various ways to estimate EAT. In this study, we investigated the predictive value of EAT thickness adjacent to the right coronary artery (RCA) for late atrial fibrillation (AF) recurrences in patients treated with cryoballoon ablation (CBA). We propose that this method is simpler than other methods for measurement of EAT on multidetector computed tomography (MDCT) images.

Method: Patients with symptomatic paroxysmal or persistent AF despite ≥ 1 antiarrhythmic drugs who were scheduled for CBA were prospectively recruited. Multidetector computed tomography was performed and epicardial adipose tissue thickness was measured as the fat-thickness from  the epicardium to the myocardium around the RCA just after the acute marginal branch. The duration of follow-up was 12 months and AF recurrence was defined as an episode of AF longer than 30 seconds duration occurring three months after CBA. The study population included 72 patients and in 22 patients (30.5%) AF recurrence was observed.

Results: Epicardial adipose tissue thickness was significantly higher in patients who had late recurrent AF compared to the patients without late recurrence (12.3 ± 3.2 vs 10.2 ± 3.2, p < 0.01). Highly sensitive C-reaction protein (Hs-CRP) level and left atrial (LA) volume index were significantly higher in the recurrent AF group compared to patients without AF recurrence.  Multivariable analysis showed that LA volume index (OR 1.41, 95% CI:1.15, 1.73, p < 0.01), hs-CRP (OR 1.42, 95% CI:1.02, 1.94, p = 0.04) and EAT thickness (OR 1.34, 95% CI:1.05, 1.71, p = 0.02) remained as independent predictors of AF recurrence in the study population.

Conclusion: Epicardial adipose tissue thickness adjacent to the RCA is associated with late AF recurrences in patients treated with CBA. This method of EAT quantification seems to be simpler, less time consuming and may be an alternative to other methods of EAT measurement.