title: Quantification of nonculprit coronary lesions: comparison of cardiac 64-MDCT and invasive coronary angiography.
abstract: OBJECTIVE
  The purpose of our study was to evaluate the accuracy of cardiac 64-MDCT to quantify the grade of stenosis of nonculprit lesions.
  
  
  METHODS
  Twenty-nine consecutive patients (23 men and six women; mean age, 62 +/- 10 years) presenting with acute coronary syndrome (ACS) had nonculprit coronary lesions of >or= 30% stenosis quantified on quantitative coronary angiography (QCA). Five 64-MDCT postprocessing techniques (maximum intensity projection [MIP], multiplanar reformat [MPR], cross-sectional area [CSA], and diameter and area derived from semiquantitative coronary software) were used to grade lesions. Two separate groups of two independent readers analyzed QCA and cardiac CT images using a 17-segment model. Coronary angiography was the reference standard.
  
  
  RESULTS
  Nonculprit lesions were identified in 46 analyzable coronary segments. Subgrouping lesions on the basis of reference vessel diameter resulted in strong correlations for quantifying nonculprit lesions in vessels > 3 mm (R = 0.78-0.91, p < 0.01) but poor correlations for nonculprit lesions in vessels <or= 3 mm (R = 0.1-0.07). Subgrouping lesions on the basis of plaque type resulted in poor correlations for calcified plaques (R = 0.01-0.30) but moderate to strong correlations for mixed (R = 0.58-0.75, p < 0.01) and noncalcified (R = 0.44-0.61, p < 0.01) plaques. The best overall correlation among all CT techniques with QCA was CSA (R = 0.56, p < 0.01). Interobserver agreement (kappa values) for MPR, MIP, coronary software diameter and area were 0.6, 0.7, 0.62, and 0.57, respectively.
  
  
  CONCLUSIONS
  In patients presenting with ACS, 64-MDCT provided an accurate grade of stenosis for nonculprit coronary lesions in proximal coronary segments. Calcified plaques and lesions in coronary segments <or= 3 mm diameter remained difficult to accurately quantify.
authors.affiliation: Department of Radiology, St. Vincent's University Hospital, Elm Park, Dublin 4, Ireland. j.dodd@st-vincents.ie
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Dodd
authors.forename: Johannes
authors.initials: J
authors.lastname: Rieber
authors.forename: Eugene
authors.initials: E
authors.lastname: Pomerantsev
authors.forename: Vithaya
authors.initials: V
authors.lastname: Chaithiraphan
authors.forename: Stephan
authors.initials: S
authors.lastname: Achenbach
authors.forename: Javier M
authors.initials: JM
authors.lastname: Moreiras
authors.forename: Suhny
authors.initials: S
authors.lastname: Abbara
authors.forename: Udo
authors.initials: U
authors.lastname: Hoffmann
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Brady
authors.forename: Ricardo C
authors.initials: RC
authors.lastname: Cury
mesh_terms: D054058:Acute Coronary Syndrome / Q000000981:diagnostic imaging* / Q000628:therapy; D000328:Adult; D000368:Aged; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000628:therapy; D005260:Female; D006801:Humans; D007479:Iopamidol; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007479:Iopamidol