Abstract 2706: Pericardial Fat Accumulation Rather Than Abdominal Obesity Associated With Atrial Fibrillation: Analysis of Pericardial Fat Volume in Patients With Atrial Fibrillation Using Computed Tomography
Background: Previous reports showed that the obesity is an important risk factor for atrial fibrillation (AF). But, the detailed mechanism that obesity contributes to AF has not been clarified. Recent studies suggest that epicardial adipose tissue may have a direct influence on coronary atherosclerosis through “vasocrine signaling” or “paracrine signaling”. Thus, we hypothesized that the epicardial adipose tissue might affect atrial muscle directly through adipokines, such as IL-6 and TNF-α, and that the inflammation caused by adipokines might lead to the pathogenic process of the AF.
Objective: The purpose of this study was to examine the association of pericardial fat with AF.
Methods: The present study comprised of 133 patients who underwent computed tomography (CT) in our hospital between April 2006 and March 2009. Pericardial fat was assessed by measuring the total pericardial fat volume (PFV) using 64-detector CT (Brilliance-64, Phillips Medical Systems, Cleveland, OH). We compared PFV between 24 patients with paroxysmal AF (AF group, 15 men; mean age, 65±12 years; range, 47– 81 years) and 109 patients without AF (control group, 63 men; mean age, 65±10 years; range, 43–79 years). PFV was measured three-dimensionally in all patients using the contrast-enhanced images. PFV was defined as any adipose tissue located within the pericardial sac.
Results: PFV correlated with age (p = 0.02), body weight (P = 0.02), body mass index (p < 0.001) by multivariate regression analysis. PFV level was significantly higher in AF group compared with control group (168.6±56.1 vs. 147.5±35.1 cm3, P = 0.02). Multivariate backward logistic regression analysis demonstrated that PFV, but not body weight, body mass index, nor waist circumference, significantly contributed to the presence of AF (odds ratio; 1.10, 95% confidence interval; 1.00 –1.26; per 10cm3 increase, P = 0.047).
Conclusions: Pericardial fat correlated with AF independently. These findings may support the hypothesis that pericardial fat depots directly related the pathogenic process of AF.