title: Computed tomographic angiography characteristics of atherosclerotic plaques subsequently resulting in acute coronary syndrome.
abstract: OBJECTIVE
  In a computed tomographic (CT) angiography study, we identified the characteristics of atherosclerotic lesions that were associated with subsequent development of acute coronary syndrome (ACS).
  
  
  BACKGROUND
  The CT characteristics of culprit lesions in ACS include positive vessel remodeling (PR) and low-attenuation plaques (LAP). These 2 features have been observed in the lesions that have already resulted in ACS, but their prospective relation to ACS has not been previously described.
  
  
  METHODS
  In 1,059 patients who underwent CT angiography, atherosclerotic lesions were analyzed for the presence of 2 features: PR and LAP. The remodeling index, and plaque and LAP areas and volumes were calculated. The plaque characteristics of lesions resulting in ACS during the follow-up of 27 +/- 10 months were evaluated.
  
  
  RESULTS
  Of the 45 patients showing plaques with both PR and LAP (2-feature positive plaques), ACS developed in 10 (22.2%), compared with 1 (3.7%) of the 27 patients with plaques displaying either feature (1-feature positive plaques). In only 4 (0.5%) of the 820 patients with neither PR nor LAP (2-feature negative plaques) did ACS develop. None of the 167 patients with normal angiograms had acute coronary events (p < 0.001). ACS was independently predicted by PR and/or LAP (hazard ratio: 22.8, 95% confidence interval: 6.9 to 75.2, p < 0.001). Among 2- or 1-feature positive segments, those resulting in ACS demonstrated significantly larger remodeling index (126.7 +/- 3.9% vs. 113.4 +/- 1.6%, p = 0.003), plaque volume (134.9 +/- 14.1 mm(3) vs. 57.8 +/- 5.7 mm(3), p < 0.001), LAP volume (20.4 +/- 3.4 mm(3) vs. 1.1 +/- 1.4 mm(3), p < 0.001), and percent LAP/total plaque area (21.4 +/- 3.7 mm(2) vs. 7.7 +/- 1.5 mm(2), p = 0.001) compared with segments not resulting in ACS.
  
  
  CONCLUSIONS
  The patients demonstrating positively remodeled coronary segments with low-attenuation plaques on CT angiography were at a higher risk of ACS developing over time when compared with patients having lesions without these characteristics.
authors: Department of Cardiology, Fujita Health University School of Medicine, Toyoake, Japan. sadakom@fujita-hu.ac.jp
authors: Sadako
authors: S
authors: Motoyama
authors: Masayoshi
authors: M
authors: Sarai
authors: Hiroto
authors: H
authors: Harigaya
authors: Hirofumi
authors: H
authors: Anno
authors: Kaori
authors: K
authors: Inoue
authors: Tomonori
authors: T
authors: Hara
authors: Hiroyuki
authors: H
authors: Naruse
authors: Junichi
authors: J
authors: Ishii
authors: Hitoshi
authors: H
authors: Hishida
authors: Nathan D
authors: ND
authors: Wong
authors: Renu
authors: R
authors: Virmani
authors: Takeshi
authors: T
authors: Kondo
authors: Yukio
authors: Y
authors: Ozaki
authors: Jagat
authors: J
authors: Narula
mesh_terms: D054058:Acute Coronary Syndrome / Q000209:etiology*; D000368:Aged; D050197:Atherosclerosis / Q000145:classification / Q000150:complications / Q000000981:diagnostic imaging*; D002114:Calcinosis / Q000000981:diagnostic imaging; D017023:Coronary Angiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed