title: Comparison of image characteristics of plaques in culprit coronary arteries by 64 slice CT and intravascular ultrasound in acute coronary syndromes.
abstract: OBJECTIVE
  To evaluate plaque image characteristics in coronary artery culprit-lesions in subjects with acute coronary syndromes (ACS), we retrospectively compared coronary arterial images by 64-slice CT before conventional-coronary-angiogram with those by intravascular ultrasound (IVUS).
  
  
  METHODS
  Retrospective analysis of coronary arterial images from thirty-one subjects (26-males, mean age 59.3 ± 12.0 years) exhibiting acute symptoms with suspicion of ACS, where either (1) ECG was un-interpretable or (2) ECG was non diagnostic/cardiac biomarkers was equivocal; with significant stenosis on emergent 64 slice CT and subjects were finally diagnosed as having ACS confirmed by conventional-coronary-angiogram, followed by IVUS before coronary-intervention. After principal culprit-lesion components were classified into 1) thrombus, 2) soft plaques, and 3) fibrotic plaques by IVUS, corresponding culprit-lesion CT values were measured (two-observers).
  
  
  RESULTS
  Nineteen and 12 of 31 subjects were finally diagnosed as unstable angina pectoris and non-ST elevation acute myocardial infarction respectively. Main culprit-lesion components of ACS were identified on MSCT in all subjects. Culprit-lesion CT values diagnosed as soft plaques by IVUS (n=6, 32.9 ± 8.7 HU) were not lower than those of thrombi (n=18, 43.2 ± 10.7 HU, p=0.268); both values were significantly lower than those of fibrotic plaques (n=7, 82.5 ± 22.6 HU) (both p<0.01). Calcification, spotty calcification, and positive arterial remodeling were observed in 67.7%, 61.3%, 58.1% (IVUS) and 58.1%, 51.6%, 74.2% (MSCT), respectively (all p=NS). CT value reproducibilities and culprit-lesion areas, were 0.87 and 0.86, respectively (two analyzers).
  
  
  CONCLUSIONS
  64-slice CT can non-invasively evaluate image characteristics in coronary artery culprit-lesions in ACS subjects accurately; this may help to differentiate soft plaques or thrombi generated by plaque rupture from fibrotic plaques.
authors.affiliation: Department of Cardiovascular Science and Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba 260-8670, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Takaoka
authors.forename: Iwao
authors.initials: I
authors.lastname: Ishibashi
authors.forename: Masae
authors.initials: M
authors.lastname: Uehara
authors.forename: Geoffrey D
authors.initials: GD
authors.lastname: Rubin
authors.forename: Issei
authors.initials: I
authors.lastname: Komuro
authors.forename: Nobusada
authors.initials: N
authors.lastname: Funabashi
mesh_terms: D054058:Acute Coronary Syndrome / Q000150:complications*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000150:complications* / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000150:complications* / Q000175:diagnosis*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional