title: Epicardial adipose tissue volume but not density is an independent predictor for myocardial ischemia.
abstract: BACKGROUND
  Epicardial adipose tissue (EAT) volume is associated with plaque formation and cardiovascular event risk, its density may reflect tissue composition and metabolic activity.
  
  
  OBJECTIVE
  Global and regional associations between EAT volume and density, ischemia and coronary calcium were investigated using a novel automatic quantitative measurement software.
  
  
  METHODS
  71 patients with an intermediate pre-test probability for coronary artery disease and inducible ischemia by SPECT were matched to two same-gender controls (total of 213 patients, 90% male, age 60 ± 10 years). Non-contrast CT for assessment of EAT volume, density (in Hounsfield Unit [HU]) and coronary calcium score (CCS) was performed.
  
  
  RESULTS
  Global EAT volume was significantly increased in ischemic patients compared to controls (96 ± 49 vs. 82 ± 36 cm(3), p = 0.04), density showed no significant difference (-75.6 ± 4.3 vs. -75.1 ± 4.1HU, p = 0.63). EAT volume and density differed significantly between coronary territories (LAD: 37 ± 18 cm(3), -77.8 ± 4.5HU; LCx: 16 ± 9 cm(3), -73.9 ± 4.1HU; RCA: 36 ± 17 cm(3), -71.7 ± 4.8HU, p < 0.001). For regional ischemia, only LCx territory showed a significantly higher EAT volume (18 ± 8 vs. 16 ± 9 cm(3), p = 0.048). Multivariable logistic regression revealed a significant association with ischemia for EAT volume (OR 2.09 (1.0; 4.3), p = 0.049) and CCS (OR 1.43 (1.1; 1.9), p = 0.006). EAT volume significantly improved discrimination of ischemia over CCS (Integrated Discrimination Improvement: 3.5%, 95%CI: 1.1-6.1%, p = 0.004). Hypertension was the only risk factor significantly influencing EAT volume and density (98 ± 48 vs. 78 ± 31 cm(3), p = 0.002, -76.0 ± 4.1 vs. -74.5 ± 4.1 HU, p = 0.01).
  
  
  CONCLUSIONS
  EAT volume is associated with myocardial ischemia and improves the discriminative power for independent ischemia prediction over CCS. In hypertensive patients, EAT is characterized by lower density and higher volumes.
authors.affiliation: Department of Cardiology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany. Electronic address: michaela.hell@uk-erlangen.de.
authors.forename: Michaela M
authors.initials: MM
authors.lastname: Hell
authors.affiliation: Computer Science Department, Henry Samueli School of Engineering and Applied Science at UCLA, Los Angeles, CA, USA. Electronic address: sjtu.xiaowei@gmail.com.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Ding
authors.affiliation: Cedars-Sinai Medical Center, Departments of Imaging and Medicine, Division of Cardiology and the Cedars-Sinai Heart Institute, Los Angeles, CA, USA. Electronic address: Mathieu.Rubeaux@cshs.org.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Rubeaux
authors.affiliation: Cedars-Sinai Medical Center, Departments of Imaging and Medicine, Division of Cardiology and the Cedars-Sinai Heart Institute, Los Angeles, CA, USA. Electronic address: piotr.slomka@cshs.org.
authors.forename: Piotr
authors.initials: P
authors.lastname: Slomka
authors.affiliation: Cedars-Sinai Medical Center, Departments of Imaging and Medicine, Division of Cardiology and the Cedars-Sinai Heart Institute, Los Angeles, CA, USA. Electronic address: heidi.gransar@cshs.org.
authors.forename: Heidi
authors.initials: H
authors.lastname: Gransar
authors.affiliation: Computer Science Department, Henry Samueli School of Engineering and Applied Science at UCLA, Los Angeles, CA, USA. Electronic address: dt@cs.ucla.edu.
authors.forename: Demetri
authors.initials: D
authors.lastname: Terzopoulos
authors.affiliation: Cedars-Sinai Medical Center, Departments of Imaging and Medicine, Division of Cardiology and the Cedars-Sinai Heart Institute, Los Angeles, CA, USA. Electronic address: sean.hayes@cshs.org.
authors.forename: Sean
authors.initials: S
authors.lastname: Hayes
authors.affiliation: Department of Cardiology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany. Electronic address: mohamed.marwan@uk-erlangen.de.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Marwan
authors.affiliation: Department of Cardiology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany. Electronic address: stephan.achenbach@uk-erlangen.de.
authors.forename: Stephan
authors.initials: S
authors.lastname: Achenbach
authors.affiliation: Cedars-Sinai Medical Center, Departments of Imaging and Medicine, Division of Cardiology and the Cedars-Sinai Heart Institute, Los Angeles, CA, USA. Electronic address: daniel.berman@cshs.org.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Berman
authors.affiliation: Cedars-Sinai Medical Center, Biomedical Imaging Research Institute, Los Angeles, CA, USA. Electronic address: damini.dey@cshs.org.
authors.forename: Damini
authors.initials: D
authors.lastname: Dey
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging*; D050154:Adiposity; D000368:Aged; D001331:Automation; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000000981:diagnostic imaging; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology*; D055414:Myocardial Perfusion Imaging / Q000379:methods; D016017:Odds Ratio; D010496:Pericardium / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D012042:Registries; D012307:Risk Factors; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
keywords: Automatic quantitative measurement; Computed tomography; Coronary calcium score; Epicardial adipose tissue; Ischemia