Transesophageal magnetic resonance imaging of the aortic arch and descending thoracic aorta in patients with aortic atherosclerosis

Objectives We sought to determine the feasibility and potential of transeso phageal magnetic resonance imaging (TEMRI) for quantifying atherosclerotic plaque burden in the aortic arch and descending thoracic aorta in compariso n with transesophageal echocardiography (TEE). Background Improved morphologic assessment of atherosclerotic plaque featur es in vivo is of interest because of the potential for improved understandi ng of the pathophysiology of plaque vulnerability to rupture and progressio n to clinical events. Magnetic resonance imaging (MRI) is well suited for a therosclerotic plaque imaging. Performing MRI using a radio frequency (RF) receiver probe placed near the region of interest improves the signal-to-no ise ratio (SNR). Methods High-resolution images of the thoracic aortic wall were obtained by TEMRI in 22 subjects (8 normals, 14 with aortic atherosclerosis). In nine subjects, we compared aortic wall thickness and circumferential extent of a therosclerotic plaque measured by TEMRI versus TEE using a Bland-Altman ana lysis. Additional studies were performed in a human cadaver with pathology as an independent gold standard for assessment of atherosclerosis. Results In clinical and experimental studies, we found similar measurements for aortic plaque thickness but a relative underestimation of circumferent ial extent of atherosclerosis by TEE (p = 0.001), due in large part to the lower SNR in the near field. ConclusionsUsing TEMRI allows for quantitative assessment of thoracic aorti c atherosclerotic plaque burden. This technique provides good SNR in the ne ar held, which makes it a promising approach for detailed characterization of aortic plaque burden. (J Am Coll Cardiol 2001;37: 2031-5) (C) 2001 by th e American College of Cardiology.