title: Non-invasive half millimetre 32 detector row computed tomography angiography accurately excludes significant stenoses in patients with advanced coronary artery disease and high calcium scores.
abstract: OBJECTIVE
  To show an overall diagnostic accuracy > or = 90% for detection of > or = 50% stenoses by coronary half millimetre 32 detector row computed tomography angiography (32 x 0.5-MDCTA) in patients with advanced coronary artery disease (CAD) and a high likelihood of raised calcium scores.
  
  
  METHODS
  ECG gated 32 x 0.5-MDCTA (32 x 0.5 mm cross sections, 0.35 x 0.35 x 0.35 mm3 isotropic voxels, 400 ms rotation) was performed after injection of iodixanol (120 ml, 320 mg/ml) in 30 consecutive patients (25 men, mean (SD) age 59 (13) years, body mass index 26.2 (4.9) kg/m2). Native arteries, including > or = 1.5 mm branches, and bypass grafts were screened for > or = 50% stenoses. Stents were excluded. Conventional coronary angiography (performed 18 (12) days before 32 x 0.5-MDCTA) was analysed by quantitative coronary angiography.
  
  
  RESULTS
  Median Agatston calcium score was 510 (range 3-5066). Sensitivity, specificity, and positive and negative predictive values for detection of > or = 50% stenoses in native arteries were 76% (29 of 38), 94% (190 of 202), 71% (29 of 41), and 96% (190 of 199), respectively. Overall diagnostic accuracy was 91% (219 of 240). Due to the following artefacts 20% (69 of 352) of the vessels were excluded: motion, noise, and low contrast enhancement isolated or in combination (45 of 69 (65%)); image distortion by implantable cardioverter-defibrillator or pacemaker leads (18 of 69 (26%)); and blooming secondary to severe calcification (6 of 69 (9%)).
  
  
  CONCLUSIONS
  Coronary 32 x 0.5-MDCTA accurately excludes > or = 50% stenoses in patients with advanced CAD and high calcium scores with an overall diagnostic accuracy of 91%.
authors.affiliation: Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: M A S
authors.initials: MA
authors.lastname: Cordeiro
authors.forename: J M
authors.initials: JM
authors.lastname: Miller
authors.forename: A
authors.initials: A
authors.lastname: Schmidt
authors.forename: A C
authors.initials: AC
authors.lastname: Lardo
authors.forename: B D
authors.initials: BD
authors.lastname: Rosen
authors.forename: D E
authors.initials: DE
authors.lastname: Bush
authors.forename: J A
authors.initials: JA
authors.lastname: Brinker
authors.forename: D A
authors.initials: DA
authors.lastname: Bluemke
authors.forename: E P
authors.initials: EP
authors.lastname: Shapiro
authors.forename: J A C
authors.initials: JA
authors.lastname: Lima
mesh_terms: D000328:Adult; D000368:Aged; D016477:Artifacts; D002114:Calcinosis / Q000000981:diagnostic imaging; D009202:Cardiomyopathies / Q000000981:diagnostic imaging*; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000592:standards