Association of symptomatic atherosclerotic carotid arteries with plaque areas showing low densities on computed tomographic angiography

Abstract

Background and purpose Intraplaque hemorrhage is a key feature of vulnerable carotid atherosclerotic plaque (CAP), associated with low densities (<25 Hounsfield units [HU]) on computed tomographic angiography (CTA). This study aimed to analyze CAP on routine CTA performed in patients with symptomatic and asymptomatic carotid stenosis undergoing carotid endarterectomy (CEA) by assessing HU of the CAP area showing the lowest density (CAPALD) using radiological tools available in daily clinical practice, and to compare CAPALD values between symptomatic and asymptomatic carotids. Methods We retrospectively screened preoperative CTA scans of 206 consecutive adult patients undergoing CEA for symptomatic or asymptomatic stenosis. CAPALD values were compared between symptomatic and asymptomatic carotids. Asymptomatic carotids included arteries contralateral to the symptomatic CEA artery, and asymptomatic stenotic arteries undergoing CEA and their contralateral arteries. Carotids were excluded when there was <30% stenosis, or when CAP could not be identified or CAPALD could not be measured. Results In total, 95 symptomatic and 112 asymptomatic carotids (derived from 174 patients) were analyzed. In multivariate analysis, symptomatic arteries showed more severe stenosis (median 70% vs. 67%, p = 0.0228) and lower CAPALD values (median 17 vs. 25 HU, p = 0.049), whereas degree of stenosis and CAPALD values were not correlated (rho = −0.02, p = 0.77). HU values of <25 were more frequent in symptomatic than asymptomatic carotids (68% vs. 47%, p = 0.0022). Conclusions On CTA, symptomatic carotids are associated with CAP areas with low densities. CTA analysis of CAP may be interesting to help identify vulnerable plaques at risk for future stroke, especially in patients lacking strict indications for CEA based on the current guidelines.

Association Between Perivascular Adipose Tissue Density and Atherosclerosis in the Descending Thoracic Aorta

“…A previous study revealed that symptomatic carotids are associated with carotid atherosclerotic plaque areas with low densities on CTA, which may be useful for identifying vulnerable plaques at risk for future stroke. 29 Our results showed that PVAT radiodensity is an independent predictor of ACP, with OR of 1.263, and is independent predictors of MPBS and plaque density, with β-coefficient of .073 and −1.666, respectively.…”

Identification Markers of Carotid Vulnerable Plaques: An Update

“…While the latest literature points out that low densities (<25 HU) on CTA seem to indicate IPH. Compared with asymptomatic plaques, HU values of <25 are frequently observed in symptomatic plaques [ 157 ]. CTA can also identify and quantify neovascularization.…”