Publications

The Atlas of Cardiovascular Magnetic Resonance (CMR) is a comprehensive, four-color visual compendium of CMR images, photomicrographs, anatomic illustrations, tables, and charts paired with extensive legends and explanations drawn from the latest peer-reviewed literature. In addition to providing historical perspective and current direction for CMR, this atlas focuses on research involving coronary artery diseases and anomalies, congestive heart failure, atherosclerotic plaques, and asymptomatic disease. The Atlas details imaging techniques, including preparation, acquisition, and processing, for study of the great vessels and carotids, the peripheral vasculature, and the coronary and pulmonary veins. Also included are discussions of the role of CMR in the emergency department and in clinical cardiology and private cardiology practices. This book is an unsurpassable professional reference.

PURPOSE: To investigate blood inflow enhancement (or lack thereof) in three-dimensional (3D) cardiovascular MR for both single phase whole-heart and cine biventricular functions. MATERIALS AND METHODS: A 3D imaging sequence is proposed in which radiofrequency excitation gradient is changed without modifying image acquisition or phase/slice encoding. This imaging sequence enables direct inflow measurement while retaining static voxel signal-to-noise ratio. Inflow measurements were performed for both spoiled gradient-echo (GRE) imaging and balanced steady-state free precession (SSFP) in 18 healthy subjects. RESULTS: For single phase imaging, increasing slab thickness from 3 to 10 cm lead to 73% and 59% reductions in contrast-to-noise ratio (CNR) with GRE and SSFP, respectively. For cine acquisitions, systolic CNR was reduced by 85% and 50% for the GRE and SSFP acquisitions, respectively, while diastolic CNR was reduced by 64% and 42%. CONCLUSION: There is significant loss of CNR between blood and myocardium when using larger 3D slabs due to saturation of inflowing spins. The loss of contrast is less pronounced for SSFP than for GRE, though both acquisition techniques suffer.

PURPOSE: To develop and validate a free-breathing cardiac cine acquisition, with potential to simplify cardiac MR studies, provide registered slices, and increase spatial resolution. MATERIALS AND METHODS: A 2D free-breathing (FB) navigator-gated cine radial acquisition for cardiac function was developed that used two navigators (one placed prior to the QRS, and another 500 msec after the QRS complex, after systole) to provide complete motion-compensated assessment of systole, without loss of end-diastole. Eleven subjects were studied. RESULTS: The 2D FB method provided results visually and quantitatively similar to the 2D breath-hold (BH) methods. Comparison of volumes measured with FB to those measured by standard 2D BH cine resulted in mean bias+/-2 standard deviations of 1.0 mL+/-13.7 mL, 1.1 mL+/-7.6 mL, 3.0 g+/-18.8 g, and 0.3%+/-2.5%, for end-diastolic volume, end-systolic volume, left ventricular (LV) mass, and ejection fraction, respectively. Slice misregistration was identified in four (36%) of the BH studies, but none (0%) of the FB studies. In subjects with slice misregistration, there was greater discordance in LV volume measurements (P<0.05 for end-diastolic mass). CONCLUSION: The FB cine acquisition provided results qualitatively and quantitatively similar to 2D BH methods with improved slice registration.

OBJECTIVES: This study sought to develop cardiovascular magnetic resonance (CMR) diagnostic criteria for mitral valve prolapse (MVP) using echocardiography as the gold standard and to characterize MVP using cine CMR and late gadolinium enhancement (LGE)-CMR. BACKGROUND: Mitral valve prolapse is a common valvular heart disease with significant complications. Cardiovascular magnetic resonance is a valuable imaging tool for assessing ventricular function, quantifying regurgitant lesions, and identifying fibrosis, but its potential role in evaluating MVP has not been defined. METHODS: To develop CMR diagnostic criteria for MVP, characterize mitral valve morphology, we analyzed transthoracic echocardiography and cine CMR images from 25 MVP patients and 25 control subjects. Leaflet thickness, length, mitral annular diameters, and prolapsed distance were measured. Two- and three-dimensional LGE-CMR images were obtained in 16 MVP and 10 control patients to identify myocardial regions of fibrosis in MVP. RESULTS: We found that a 2-mm threshold for leaflet excursion into the left atrium in the left ventricular outflow tract long-axis view yielded 100% sensitivity and 100% specificity for CMR using transthoracic echocardiography as the clinical gold standard. Compared with control subjects, CMR identified MVP patients as having thicker (3.2 +/- 0.1 mm vs. 2.3 +/- 0.1 mm) and longer (10.5 +/- 0.5 mm/m(2) vs. 7.1 +/- 0.3 mm/m(2)) indexed posterior leaflets and larger indexed mitral annular diameters (27.8 +/- 0.7 mm/m(2) vs. 21.5 +/- 0.5 mm/m(2) for long axis and 22.9 +/-0.7 mm/m(2) vs. 17.8 +/- 0.6 mm/m(2) for short axis). In addition, we identified focal regions of LGE in the papillary muscles suggestive of fibrosis in 10 (63%) of 16 MVP patients and in 0 of 10 control subjects. Papillary muscle LGE was associated with the presence of complex ventricular arrhythmias in MVP patients. CONCLUSIONS: Cardiovascular magnetic resonance image can identify MVP by the same echocardiographic criteria and can identify myocardial fibrosis involving the papillary muscle in MVP patients. Hyperenhancement of papillary muscles on LGE is often present in a subgroup of patients with complex ventricular arrhythmias.