Characterization of Coronary Atherosclerosis by Magnetic Resonance Imaging

Coronary atherosclerosis remains the major cause of mortality in industrialized and developing nations.1 Clinical risk-scoring systems do not allow satisfactory identification of individuals with subclinical disease and at high risk for coronary events.2 Novel approaches to more reliably identify asymptomatic individuals at high risk for future cardiovascular events are therefore urgently needed.Subclinical atherosclerosis may precede the development of clinical disease by many decades, thereby offering the opportunity to target primary prevention therapies to those at highest risk.3 Because of its noninvasiveness, excellent soft-tissue contrast, and ability to visualize blood and the coronary vessel wall with and without contrast agents, magnetic resonance (MR) imaging (MRI) is a very promising imaging modality to assess coronary lumen integrity, plaque burden, and biological plaque composition. Studies investigating subclinical and clinical coronary atherosclerosis have included non–contrast-enhanced (NCE) and contrast-enhanced (CE) coronary vessel wall cardiovascular MR (CMR).Recent studies have shown that noninvasive MR angiography allows the assessment of the presence or absence of >50% coronary artery stenosis with a diagnostic accuracy comparable to that of multidetector computer tomography if performed in a head-to-head comparison and with similar pharmacological preparation.4,5 Technical improvements in coil design, image acquisition and reconstruction, and motion compensation have allowed shortening the total imaging time of whole-heart coronary MR angiography to ≈5 minutes while maintaining good diagnostic accuracy.6–8 Several single-center and multicenter trials have demonstrated the potential of this technique compared with both x-ray coronary angiography and multidetector computer tomography.4,9,10Direct assessment of the coronary vessel wall thickness and remodeling has been demonstrated with NCE-CMR in patients with subclinical coronary artery disease, in patients with type 1 diabetes mellitus, and in a multiethnic population (Multi-Ethnic Study of Atherosclerosis [MESA]) cohort.11–13 Additionally, NCE-CMR has been …