Impact of epicardial fat volume on coronary artery disease in symptomatic patients with a zero calcium score

Background: This study sought to evaluate the prevalence of coronary artery disease (CAD) and the impact of epicardial fat volume (EFV) on CAD in symptomatic patients with a zero calcium score (CS) using multislice computed tomography (MSCT). Methods: In this study, 1308 consecutive symptomatic patients who underwent 64-slice MSCT with a zero CS were evaluated. EFV was quantified with CS data sets. Presence of an obstructive plaque (diameter stenosis >50%) and a CT-derived vulnerable plaque, which was defined as a plaque with remodeling index >1.10 and mean CT density value <30 HU, was assessed with a CT coronary angiography. Results: Obstructive plaques were detected in 86 patients (7%) and CT-derived vulnerable plaques in 63 (5%). EFV was larger in patients with obstructive plaques than no plaque (124.3 +/- 43.2 cm(3) vs. 95.1 +/- 40.3 cm(3); p<0.01). Patients with CT-derived vulnerable plaques had a greater amount of EFV than no plaque (133.0 +/- 40.2 cm(3) vs. 95.1 +/- 40.3 cm(3); p<0.01). Multivariate analysis revealed EFV as a predictor of the presence of an obstructive and a CT-derived vulnerable plaque (per 10 cm(3); Odds ratio (OR) 1.10; 95% confidence interval (CI), 1.04-1.16; p<0.01 and OR 1.19; 95% CI, 1.12-1.27; p<0.01). The combination of EFV and Framingham risk score (FRS) resulted in an area under the receiver-operating characteristic curve for prediction of obstructive and CT-derived vulnerable plaque of 0.75 and 0.75, which was significantly higher than 0.68 and 0.64 for FRS alone (p=0.02 and p<0.01). Conclusions: A zero CS doesn't exclude CAD and EFV can be a useful marker of CAD in symptomatic zero CS patients. (C) 2012 Elsevier Ireland Ltd. All rights reserved.