Three-dimensional black-blood cardiac magnetic resonance coronary vessel wall imaging detects positive arterial remodeling in patients with nonsignificant coronary artery disease

Abstract

Background - Direct noninvasive visualization of the coronary vessel wall may enhance risk stratification by quantifying subclinical coronary atherosclerotic plaque burden. We sought to evaluate high-resolution black-blood 3D cardiovascular magnetic resonance (CMR) imaging for in vivo visualization of the proximal coronary artery vessel wall. Methods and Results - Twelve adult subjects, including 6 clinically healthy subjects and 6 patients with nonsignificant coronary artery disease (10% to 50% x-ray angiographic diameter reduction) were studied with the use of a commercial 1.5 Tesla CMR scanner. Free-breathing 3D coronary vessel wall imaging was performed along the major axis of the right coronary artery with isotropic spatial resolution (1.0×1.0 ×1.0 mm3) with the use of a black-blood spiral image acquisition. The proximal vessel wall thickness and luminal diameter were objectively determined with an automated edge detection tool. The 3D CMR vessel wall scans allowed for visualization of the contiguous proximal right coronary artery in all subjects. Both mean vessel wall thickness (1.7±0.3 versus 1.0±0.2 mm) and wall area (25.4±6.9 versus 11.5±5.2 mm2) were significantly increased in the patients compared with the healthy subjects (both P<0.01). The lumen diameter (3.6±0.7 versus 3.4±0.5 mm, P=0.47) and lumen area (8.9±3.4 versus 7.9±3.5 mm2, P=0.47) were similar in both groups. Conclusions - Free-breathing 3D black-blood coronary CMR with isotropic resolution identified an increased coronary vessel wall thickness with preservation of lumen size in patients with nonsignificant coronary artery disease, consistent with a "Giagov-type" outward arterial remodeling. This novel approach has the potential to quantify subclinical disease.