Abstract 11225: Co-existing Multiple Vulnerable Plaque Characteristic Factors in Single Non-Obstructive Non Calcified or Mixed Plaques in Coronary Arteries on CT Could Predict Occurrence of Major Cardiac Events on Follow-up for a Median of 103 Months
Purpose: To evaluate significance of presence of three vulnerable plaque characteristics (VPC) co-existing in single non calcified plaques (NCP) or mixed plaques (MP) in non obstructed coronary arteries on CT: 1) low attenuation (LA) (< 30HU), 2) positive remodeling (PR) and 3) spotty calcification (SC), for risk of major adverse cardiac events (MACE).
Methods: 166 consecutive subjects with suspected coronary artery disease (81 male; 62 ± 13 years; hypertension, 61%; diabetes mellitus, 21%; dyslipidemia, 56%; smokers, 45%; obese, 49%) underwent cardiac CT from 2003 to 2004. On CT no significant stenosis (≥ 50%) of coronary arteries was observed; subjects were retrospectively followed for a median of 103 months after CT and incidence of MACE was compared. Subjects with old myocardial infarction or myocardial diseases were excluded.
Results: 39 subjects had NCP (17) or MP (22), of whom 8, 29, and 14 subjects had LA, PR, and SC in NCP or MP, respectively. These were classified into 4 groups, 1) 128 who did not have NCP or MP with any VPCs, 2) 20 who had NCP or MP with one VPC, 3) 14 who had NCP or MP with two VPCs and 4) 2 who had NCP or MP with three VPCs. 6 subjects (4%) had MACE. Subjects who had NCP or MP with ≥ two VPCs (n=16) had a higher risk of MACE than subjects with ≤ one VPC (n=150) (P < 0.05). Significant differences between subjects with NCP or MP with ≥ two VPCs and others (zero, one VPC groups) were observed by Kaplan Meier analysis and log rank test (P < 0.001). A Cox proportional hazard model revealed that presence of NCP or MP with ≥ two VPCs was a greater predictor of MACE (Hazard ratio 7.5, P < 0.05) than other factors.
Conclusions: Presence of NCP or MP with ≥ two VPCs in non obstructed coronary arteries on CT were critical factors for the prediction of MACE in subjects with normal myocardium on follow-up for a median of 103 months.
Even in subjects without significant stenosis in coronary arteries on CT, if NCP or MP with ≥ two VPCs are observed on CT, careful follow-up with control of risk factors is desired.
- © 2013 by American Heart Association, Inc.