Computed tomographic angiography characteristics of atherosclerotic plaques subsequently resulting in acute coronary syndrome.
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.
Motoyama
Sadako
S
Department of Cardiology, Fujita Health University School of Medicine, Toyoake, Japan. sadakom@fujita-hu.ac.jp
Sarai
Masayoshi
M
Harigaya
Hiroto
H
Anno
Hirofumi
H
Inoue
Kaori
K
Hara
Tomonori
T
Naruse
Hiroyuki
H
Ishii
Junichi
J
Hishida
Hitoshi
H
Wong
Nathan D
ND
Virmani
Renu
R
Kondo
Takeshi
T
Ozaki
Yukio
Y
Narula
Jagat
J
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