Differences in carotid arterial morphology and composition between individuals with and without obstructive coronary artery disease: A cardiovascular magnetic resonance study

Objective We sought to determine differences with cardiovascular magnetic resonance (CMR) in the morphology and composition of the carotid arteries between individuals with angiographically-defined obstructive coronary artery disease (CAD, ≥ 50% stenosis, cases) and those with angiographically normal coronaries (no lumen irregularities, controls). Methods and results 191 participants (50.3% female; 50.8% CAD cases) were imaged with a multi-sequence, carotid CMR protocol at 1.5T. For each segment of the carotid, lumen area, wall area, total vessel area (lumen area + wall area), mean wall thickness and the presence or absence of calcification and lipid-rich necrotic core were recorded bilaterally. In male CAD cases compared to male controls, the distal bulb had a significantly smaller lumen area (60.0 ± 3.1 vs. 79.7 ± 3.2 mm 2 , p < 0.001) and total vessel area (99.6 ± 4.0 vs. 119.8 ± 4.1 mm 2 ; p < 0.001), and larger mean wall thickness (1.25 ± 0.03 vs. 1.11 ± 0.03 mm; p = 0.002). Similarly, the internal carotid had a smaller lumen area (37.5 ± 1.8 vs. 44.6 ± 1.8 mm 2 ; p = 0.006) and smaller total vessel area (64.0 ± 2.3 vs. 70.9 ± 2.4 mm 2 ; p = 0.04). These metrics were not significantly different between female groups in the distal bulb and internal carotid or for either gender in the common carotid. Male CAD cases had an increased prevalence of lipid-rich necrotic core (49.0% vs. 19.6%; p = 0.003), while calcification was more prevalent in both male (46.9% vs. 17.4%; p = 0.002) and female (33.3% vs. 14.6%; p = 0.031) CAD cases compared to controls. Conclusion Males with obstructive CAD compared to male controls had carotid bulbs and internal carotid arteries with smaller total vessel and lumen areas, and an increased prevalence of lipid-rich necrotic core. Carotid calcification was related to CAD status in both males and females. Carotid CMR identifies distinct morphological and compositional differences in the carotid arteries between individuals with and without angiographically-defined obstructive CAD.