Early atherosclerosis detection in asymptomatic patients: a comparison of carotid ultrasound, coronary artery calcium score, and coronary computed tomography angiography.

Background: Detailed multimodality assessment of subclinical atherosclerosis in asymptomatic subjects referred for risk stratification has not been performed. We analyzed the detection of early atherosclerosis using 3 imaging modalities: coronary artery calcium (CAC) scoring, carotid ultrasound (US), and coronary computed tomography angiography (CCTA).
Methods: Asymptomatic subjects free of known vascular disease scheduled to undergo a carotid US for risk stratification were invited to undergo CCTA/CAC. Subjects taking lipid-lowering medication were excluded. All images were assessed by experienced core laboratory personnel. Carotid intima media thickness ≥ 75th percentile for age and sex, CAC > 0, and detection of either carotid or coronary artery plaque were indicators of atherosclerosis.
Results: Fifty patients were included with a median age of 53 years. Atherosclerosis was observed in 28%, 78%, and 90% of subjects using CAC, CCTA, and carotid US, respectively. All subjects showed atherosclerosis on at least 1 modality. In 36 patients with a CAC score = 0, 69% and 86% had atherosclerosis on CCTA and carotid US, respectively.
Conclusions: In this detailed analysis, all subjects identified to warrant further risk stratification had subclinical atherosclerosis on at least 1 imaging modality. Concordance between modalities was highly variable, dependent on the specific definition of atherosclerosis used. Carotid US and CCTA detection of plaque were significantly more sensitive than CAC > 0 in this middle-aged population. Considering the prevalence of subclinical disease on carotid US and CCTA, the threshold at which to treat warrants further research.
(Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)