The different association of epicardial fat with coronary plaque in patients with acute coronary syndrome and patients with stable angina pectoris: analysis using integrated backscatter intravascular ultrasound.

OBJECTIVES

We assessed the hypothesis that the epicardial fat is associated with coronary lipid plaque.

BACKGROUND

Epicardial fat volume (EFV) is increased in patients with acute coronary syndrome (ACS), and lipid-rich plaques have been associated with acute coronary events.

METHODS

We enrolled 112 individuals who underwent percutaneous coronary intervention (PCI) (66 with ACS; 46 with stable angina pectoris [SAP]) and classified plaque components using integrated backscatter intravascular ultrasound as calcified, fibrous, or lipid. Possible effects of PCI on plaque data were minimized by assessing 10-mm vessel lengths proximal to the culprit lesions. Total plaque volume and percentage volumes of individual plaque components were calculated. EFV and abdominal visceral fat area were measured using 64-slice computed tomography.

RESULTS

ACS patients had significantly higher EFV than did SAP patients (118 ± 44 vs.101 ± 41 mL, p = 0.019). In ACS patients, EFV was correlated with total plaque volume and percentage of lipid plaque (r = 0.27 and 0.31, respectively; p < 0.05). Moreover, an independent interaction between EFV and lipid-rich plaque (odds ratio, 1.04; 95% confidence interval, 1.00-1.07) were revealed. In contrast, in SAP patients, EFV was positively correlated with body mass index and abdominal visceral fat area but not with plaque characteristics.

CONCLUSIONS

EFV was associated with lipid-rich plaque in patients with ACS, whereas no correlation between EFV and coronary plaque profile was apparent in SAP patients. Epicardial fat may have a role in the development of lipid plaque, which contributes to the pathogenesis of ACS.