title: Coronary artery stenoses: accuracy of 64-detector row CT angiography in segments with mild, moderate, or severe calcification--a subanalysis of the CORE-64 trial.
abstract: OBJECTIVE
  To evaluate the influence of cross-sectional arc calcification on the diagnostic accuracy of computed tomography (CT) angiography compared with conventional coronary angiography for the detection of obstructive coronary artery disease (CAD).
  
  
  METHODS
  Institutional Review Board approval and written informed consent were obtained from all centers and participants for this HIPAA-compliant study. Overall, 4511 segments from 371 symptomatic patients (279 men, 92 women; median age, 61 years [interquartile range, 53-67 years]) with clinical suspicion of CAD from the CORE-64 multicenter study were included in the analysis. Two independent blinded observers evaluated the percentage of diameter stenosis and the circumferential extent of calcium (arc calcium). The accuracy of quantitative multidetector CT angiography to depict substantial (≥ 50%) stenoses was assessed by using quantitative coronary angiography (QCA). Cross-sectional arc calcium was rated on a segment level as follows: noncalcified or mild (< 90°), moderate (90°-180°), or severe (> 180°) calcification. Univariable and multivariable logistic regression, receiver operation characteristic curve, and clustering methods were used for statistical analyses.
  
  
  RESULTS
  A total of 1099 segments had mild calcification, 503 had moderate calcification, 338 had severe calcification, and 2571 segments were noncalcified. Calcified segments were highly associated (P < .001) with disagreement between CTA and QCA in multivariable analysis after controlling for sex, age, heart rate, and image quality. The prevalence of CAD was 5.4% in noncalcified segments, 15.0% in mildly calcified segments, 27.0% in moderately calcified segments, and 43.0% in severely calcified segments. A significant difference was found in area under the receiver operating characteristic curves (noncalcified: 0.86, mildly calcified: 0.85, moderately calcified: 0.82, severely calcified: 0.81; P < .05).
  
  
  CONCLUSIONS
  In a symptomatic patient population, segment-based coronary artery calcification significantly decreased agreement between multidetector CT angiography and QCA to detect a coronary stenosis of at least 50%.
authors.affiliation: Department of Cardiology, Johns Hopkins Hospital, Baltimore, MD 21287, USA.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Vavere
authors.forename: Armin
authors.initials: A
authors.lastname: Arbab-Zadeh
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Rochitte
authors.forename: Marc
authors.initials: M
authors.lastname: Dewey
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Niinuma
authors.forename: Ilan
authors.initials: I
authors.lastname: Gottlieb
authors.forename: Melvin E
authors.initials: ME
authors.lastname: Clouse
authors.forename: David E
authors.initials: DE
authors.lastname: Bush
authors.forename: John W M
authors.initials: JW
authors.lastname: Hoe
authors.forename: Albert
authors.initials: A
authors.lastname: de Roos
authors.forename: Christopher
authors.initials: C
authors.lastname: Cox
authors.forename: João A C
authors.initials: JA
authors.lastname: Lima
authors.forename: Julie M
authors.initials: JM
authors.lastname: Miller
mesh_terms: D000368:Aged; D002114:Calcinosis / Q000000981:diagnostic imaging*; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed