title: A clinical model to identify patients with high-risk plaque by coronary computed tomography angiography.
abstract: OBJECTIVE
  Current clinical models predict the pre-test probability of obstructive coronary artery disease, but these models do not predict the presence of high-risk plaques. Thus the objective of this study was to propose a model to predict high-risk plaque assessed by coronary computed tomography (CT) angiography.
  
  
  METHODS
  This study was a retrospective cross-sectional study. A clinical model was derived from 2392 patients and verified by 733 patients who underwent coronary CT suspected of coronary artery disease. High-risk plaque was defined as a plaque with positive remodeling (remodeling index>1.1), low attenuation (<30Hounsfield units) and napkin-ring sign. The risk score was calculated from the following 6 variables with a maximum of 24 points: age, sex, hemoglobin A1c, systolic blood pressure, high-density lipoprotein and smoking status.
  
  
  RESULTS
  The proportion of patients with high-risk plaque was 11% and 17% in the derivation and validation cohort, respectively. The area under the receiver operation characteristic curve was 0.71 (95% confidence interval (CI): 0.68 to 0.74) in the derivation cohort and 0.75 (95% CI: 0.70 to 0.79) in the validation cohort. The frequency of high-risk plaques was 4% in the low-risk group (≤8 points) while it was 53% in the high-risk group (≥17 points) of the derivation cohort.
  
  
  CONCLUSIONS
  We propose a scoring system to detect high-risk plaque assessed by coronary CT. Patients in the high-risk group have a high prevalence of high-risk plaque and might benefit from lipid lowering therapy.
authors.affiliation: Department of Radiology, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba 270-2232, Japan. Electronic address: tomizawa-tky@umin.ac.jp.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Tomizawa
authors.affiliation: Department of Radiology, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba 270-2232, Japan.
authors.forename: Kodai
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Department of Radiology, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba 270-2232, Japan.
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Hayakawa
authors.affiliation: Department of Radiology, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba 270-2232, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Inoh
authors.affiliation: Department of Radiology, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba 270-2232, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nojo
authors.affiliation: Department of Cardiology, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba 270-2232, Japan.
authors.forename: Sunao
authors.initials: S
authors.lastname: Nakamura
mesh_terms: D000367:Age Factors; D000368:Aged; D019540:Area Under Curve; D000072226:Computed Tomography Angiography / Q000379:methods*; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012737:Sex Factors; D016019:Survival Analysis
keywords: Clinical model; Coronary CT angiography; High-risk plaque; Low attenuation; Napkin ring sign; Positive remodeling