Epicardial adipose tissue volume and coronary artery calcium to predict myocardial ischemia on positron emission tomography-computed tomography studies.
BACKGROUND
There appears to be an association of epicardial adipose tissue (EAT) with coronary artery disease (CAD) and its risk factors. EAT is assumed to influence CAD development by altering vasomotor tone and via toxic paracrine effects. The relationship of EAT to myocardial perfusion has not been studied.


METHODS
Quantification of EAT and CAC was performed on positron emission tomography/computed tomography (PET/CT) studies in 45 subjects (77% intermediate pre-test probability of CAD) with mild-moderate myocardial ischemia (5-14% perfusion defect, n = 23), severe ischemia (≥15% defect, n = 22) and a control group with no ischemia matched for CAD risk factors (n = 52).


RESULTS
EAT volume showed a better correlation with myocardial ischemia than total CAC (r = .47 vs r = .28, P < .01). EAT volume increased significantly from the control group to subjects with mild-moderate and severe ischemia (96.9, 124.5, and 143.9 cm(3), P < .01 for both ischemia groups vs controls). Total mean CAC was significantly higher in the severe ischemia group (676.3) than in control group (229.4) (P < .01). Multivariable logistic regression analyses showed that EAT volume was, but CAC was not, a significant predictor of ischemia after adjustment for age, sex, body mass index, and each other. EAT volume was a better predictor of ischemia than total CAC [area under the curve (AUC): .764 vs .6291, P = .04]. The combination of EAT + CAC (AUC = .7694) did not improve over EAT volume alone (P = .57).


CONCLUSIONS
In this study, EAT volume assessed by CT was an independent predictor of ischemia on PET, and outperformed CAC score in a CAD naïve population at intermediate pre-test probability of disease.
Janik
Matthew
M
Division of Cardiology, Department of Medicine, Emory University, 1365 Clifton Road, AT-504, Atlanta, GA 30322, USA.
Hartlage
Gregory
G
Alexopoulos
Nikolaos
N
Mirzoyev
Zaur
Z
McLean
Dalton S
DS
Arepalli
Chesnal D
CD
Chen
Zhengjia
Z
Stillman
Arthur E
AE
Raggi
Paolo
P
D000273:Adipose Tissue / Q000473:pathology*; D000328:Adult; D000368:Aged; D002118:Calcium / Q000378:metabolism*; D003331:Coronary Vessels / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology; D010496:Pericardium / Q000473:pathology*; D049268:Positron-Emission Tomography / Q000379:methods*; D012307:Risk Factors; D014057:Tomography, X-Ray Computed
D002118:Calcium