Epicardial adipose tissue and coronary artery plaque characteristics

Objective: Epicardial adipose tissue (EAT) has been implicated in the pathogenesis of coronary atherosclerosis. The association of EAT volume with type of coronary artery plaque on computed tomography angiography (CTA) is not known.

Methods: Coronary artery calcium (CAC) scoring and EAT volume measurement were performed on 214 consecutive patients (mean age 54+/-14 years) referred for coronary CTA. CAC was performed on non-contrast images, while EAT volume, the severity of luminal stenoses, and plaque characterization were assessed using contrast-enhanced CTA images. EAT volume was also indexed to body surface area (EAT-i).

Results: EAT volume correlated with age, height, body mass index (BMI), and CAC score. EAT volume increased significantly with the severity of luminal stenosis (p<0.001), and in patients with no plaques, calcified, mixed, and non-calcified plaques (62+/-33mL, 63+/-22mL, 98+/-47mL, and 99+/-36mL, respectively, p<0.001). The EAT volume was significantly larger in patients with mixed or non-calcified plaques compared to patients with calcified plaques or no plaques (all p<0.01 or smaller). The trend remained significant after adjustment for traditional risk factors for coronary artery disease. In adjusted models EAT was an independent predictor of CAC [exp(B)=3.916, p<0.05], atherosclerotic plaques of any type [exp(B)=4.532, p<0.01], non-calcified plaques [exp(B)=3.849, p<0.01], and obstructive CAD [exp(B)=3.824, p<0.05]. The above results were unchanged after replacing EAT with EAT-i.

Conclusion: EAT volume was larger in the presence of obstructive CAD and non-calcified plaques. These data suggest that EAT is associated with the development of coronary atherosclerosis and potentially the most dangerous types of plaques.