Positive Remodeling of the Coronary Arteries Detected by Magnetic Resonance Imaging in an Asymptomatic Population. MESA (Multi-Ethnic Study of Atherosclerosis)

Objectives: The purpose of this study was to assess coronary arterial remodeling as a marker of subclinical atherosclerosis using coronary wall magnetic resonance imaging (MRI) in an asymptomatic population-based cohort. Background: In early atherosclerosis, compensatory enlargement of both the outer wall of the vessel as well as the lumen, termed compensatory enlargement or positive remodeling, occurs before luminal narrowing. Methods: One hundred seventy-nine participants in the MESA (Multi-Ethnic Study of Atherosclerosis) trial were evaluated using black-blood coronary wall MRI. Coronary cross-sectional area (vessel size), lumen area, and mean wall thickness of the proximal coronary arteries were measured. Results: Men had a greater vessel size, lumen area, and mean wall thickness than women (38.3 ± 11.3 mm² vs. 32.6 ± 9.4 mm², 6.7 ± 3.2 mm² vs. 5.3 ± 2.4 mm², and 2.0 ± 0.3 mm vs. 1.9 ± 0.3 mm, respectively, p < 0.05). No significant coronary artery narrowing was present by magnetic resonance angiography. Overall, coronary vessel size increased 25.9 mm² per millimeter increase in coronary wall thickness, whereas lumen area increased only slightly at 3.1 mm² for every millimeter increase in wall thickness (difference in slopes, p < 0.0001). Adjusting for age and sex, participants with an Agatston score >0 were more likely to have wall thickness >2.0 mm (odds ratio: 2.0, 95% confidence interval: 1.01 to 3.84). Conclusions: Coronary wall MRI detected positive arterial remodeling in asymptomatic men and women with subclinical atherosclerosis.