Abstract 3843: The Composition and Morphology of the Carotid Artery are Associated with Coronary Artery Disease: A Case-Control High Resolution Magnetic Resonance Imaging Study
Background: To improve the prediction of cardiovascular events in asymptomatic individuals, non-invasive imaging techniques have been increasingly investigated as a potential supplement to the clinically-based risk stratification criteria. We sought to identify structural and compositional differences in the carotid arterial wall via high-resolution magnetic resonance imaging (MRI) between participants with angiographically defined obstructive coronary artery disease (CAD, > 50% stenosis, case) and those with normal coronary arteries (no lumen irregularities, control).
Methods: Ninety-four participants (56% female; 20% diabetic; 54% smokers; 55% CAD cases) who underwent coronary angiography but were not selected on the basis of carotid disease status were imaged with a multi-sequence, high-resolution carotid MRI protocol on a 1.5T scanner. Two reviewers blinded to CAD status reached a consensus interpretation for each scan. At each axial imaging location, lumen area (LA), total vessel area (TVA), wall area (WA), mean wall thickness (MWT) and normalized wall index (NWI = WA/[LA + WA]) were determined. Area measurements of calcification (CA) and lipid-rich necrotic core (LRNC) were also recorded. Results were compiled after controlling for gender and within-subject correlations among arterial sites.
Results: In the internal carotid artery (ICA), CAD cases demonstrated a smaller mean LA and TVA, while having a larger MWT, NWI and CA (Table 1⇓). In the distal bulb, CA and LRNC were larger in CAD cases (Table 1⇓). CAD cases also demonstrated a greater prevalence (9.9% vs. 2.9%, p = 0.004) of CA in the ICA. No differences between groups were identified in the common carotid artery.
Conclusions: Statistically significant structural and compositional differences in the carotid artery exist between subjects with and without CAD. These findings provide compelling evidence that carotid MRI may be an effective screening tool for identifying subjects at risk from CAD.