Abstract 15370: Evaluation of Fibrous Cap Thickness by Optical Coherence Tomography for Positive Remodeling and Low Attenuation Plaques Assessed by Computed Tomography Angiography
Positive vessel remodeling (PR) and low-attenuation plaques (LAP) by computed tomography angiography (CTA) might be associated with plaque vulnerability. The purpose of this study was assessed the relationship between coronary plaques with PR and LAP by CTA and fibrous cap thickness estimated by optical coherence tomography (OCT) in vivo.
Methods: One hundred two coronary plaques in patients with coronary artery disease (unstable angina pectoris, n= 24; stable angina pectoris, n=78) were assessed by CTA and OCT. Plaque characteristics were divided into three groups; 2 feature-positive plaques (PR and LAP), 1 feature-positive plaques (PR or LAP), and 2 feature-negative plaques (Neither PR and LAP). PR was defined as a remodeling index > 1.05 and LAP was < 50 HU.
Results: There were no significant differences in clinical characteristics among the three groups. There were significant differences among the groups classified by plaque characteristics with respect to the fibrous cap thickness estimated by OCT: 76 ± 24 μ m in 2 feature-positive plaques (n=30), 139 ± 40 μ m in 1 feature-positive plaques (n=22), and 179 ± 42 μ m in 2 feature-negative plaques (n=50) (p<0.0001). The prevalence of thin cap fibroatheroma (<65 μ m) in the 2 feature-positive plaques was significantly higher than in the other groups (50%, 0%, 0%, p<0.0001). The remodeling index and CT attenuation values of plaques were significantly correlated to the fibrous cap thickness (r=-0.64, p<0.0001 and r=0.68, p<0.0001, respectively).
Conclusions: The coronary PR and LAP by CTA was associated with the degree of the fibrous cap thickness measured by OCT. The CTA can noninvasively provide promising information on plaque vulnerability by identifying coronary plaque with PR and LAP.
- © 2011 by American Heart Association, Inc.