Rhode Island Hospital & The Miriam Hospital
Cardiovascular MRI
Indications
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• Myocardial viability
• Global and regional
ventricular function
• Quantified cavity volumes,
percent
ejection fraction,
ventricular mass
• Congenital heart disease
• Pericardial disease
• Non-ischemic cardiomyopathy
• Valvular heart disease
• Cardiac and extracardiac masses
• Bypass graft patency/
anomalous coronary
• Physiologic imaging
• Bulk flow in large vessels
•Pressure gradients across
stenotic lesions
•Shunt fraction
• Aortic, renal and peripheral
vascular disease
• Problem solving
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The Value of Cardiac MRI
Myocardial viability – Although direct visualization of atherosclerotic plaque by MRI remains limited, MRI has an unparalleled ability to precisely delineate myocardial scar associated with coronary artery disease—so called viability imaging. Importantly, viability imaging by MRI can predict the likelihood of functional improvement following revascularization.
Global and regional ventricular function – Due to high temporal and spatial resolution and superb inherent contrast between myocardium and blood pool, MRI can very precisely characterize cardiac function and accurately quantify cavity volumes, ejection fraction, and where appropriate, left ventricular mass.
Congenital heart disease – MRI is a true 3-D imaging modality and images can be obtained in any obliquity while preserving high temporal and spatial resolution. This flexibility is invaluable in the evaluation of congenital lesions. Moreover, MRI has the ability to accurately quantify flowrelated physiology, including bulk flow in vessels, pressure gradients across stenosis, regurgitant fractions and shunt fractions.
Pericardial disease – MRI readily demonstrates pericardial thickness, effusions, and associated effects on myocardial function and chamber sizes, such as those seen in constrictive pericarditis.
Non-ischemic cardiomypathy – By employing IV contrast, MRI can delineate areas of myocardial infiltration and regions of scar or fibrosis that are not due to coronary artery disease. These abnormal areas of enhancement, combined with functional information, can help characterize various cardiomyopathies such as hypertrophic cardiomyopathy, cardiac sarcoid and arrhythmogenic right ventricular dysplasia.
“One very promising clinical application of cardiac MRI is in the assessment of myocardial viability, how much myocardium is recoverable after a heart attack or an acute ischemic event. This is very important to interventional cardiologists and surgeons in developing their strategies for revascularizing different areas of the heart muscle.”
Kenneth Korr, MD
Director, division of cardiology, The Miriam Hospital
Associate professor of medicine, Brown Medical School
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Valvular heart disease – Valve morphology and area can be determined and the severity of stenosis or regurgitation quantified.
Cardiac masses – MRI has a broad arsenal of imaging techniques (i.e., pulse sequences) that permit detailed characterization of cardiac and extracardiac masses. MRI can characterize the size, mobility, site of attachment, functional significance and vascularity of masses.
Physiologic imaging – Specialized MRI methods are available to encode images with velocity information. These methods permit quantification of flow-related physiologic data, such as blood flow in the aorta or pulmonary arteries and the peak velocity across stenotic valves.
Aortic and peripheral vascular disease – High resolution anatomic imaging permits assessment of vascular wall abnormalities, such as those seen in atherosclerosis and large vessel vasculitis. When coupled with IV contrast for lumen evaluation, MRI provides comprehensive visualization of vascular pathology.
Problem solving – With an assortment of imaging techniques for 3-D anatomic and physiologic evaluation, MRI is equipped to address various specific questions that are incompletely answered using other methods.
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