Epicardial adipose tissue (EAT) is a metabolically active visceral fat, which secretes inflammatory cytokines and adipokines. In this study, our aim was to examine which measurements of EAT thickness by magnetic resonance imaging (MRI) could best help differentiate inflammatory status, classified by levels of high-sensitivity C-reactive protein (hs-CRP), in obese men with metabolic syndrome (MetS). We prospectively enrolled 32 men with central obesity (waist circumference ≥90 cm) and at least two other MetS criteria. MRI examinations for measurements of EAT, subcutaneous fat, and abdominal visceral fat as well as recordings of anthropometric parameters and tests for serum inflammatory cytokines and adipokines were conducted. Subjects with MetS (N = 32) were divided into three subgroups: (i) low inflammatory status (hs-CRP0.1 mg/dl, N = 8), [corrected] (ii) intermediate inflammatory status (hs-CRP 0.1-0.3 mg/dl, N = 15), and (iii) high inflammatory status (hs-CRP0.3 mg/dl, N = 9). EAT thickness at the right atrioventricular (AV) groove showed a significant linear trend among the three subgroups of MetS (P for trend = 0.004). High inflammatory status MetS subgroup had a significantly thicker right AV groove EAT than did the low inflammatory status MetS subgroup (19.3 ± 3.1 vs. 14.4 ± 3.3 mm, P = 0.015). In binary logistic regression analysis, right AV groove EAT thickness was an independent predictor for differentiating inflammatory status in MetS while abdominal visceral fat area and insulin-resistance index were not. In conclusion, MRI measured EAT thickness at the right AV groove could be a useful marker for differentiating the inflammatory status in obese men with MetS.
