Cyanosis MRI

CMR may be used for assessing individuals with valvular heart disease in which evaluation of valvular stenosis, regurgitation, para- or perivalvular masses, perivalvular complications of infectious processes, or prosthetic valve disease are needed. CMR may be useful in identifying serial changes in LV volumes or mass in patients with valvular dysfunction.

CMR may be used for assessment of patients with LV dysfunction or hypertrophy or suspected forms of cardiac injury not related to ischemic heart disease. When the diagnosis is unclear, CMR may be considered to identify the etiology of cardiac dysfunction in patients presenting with heart failure, including

• evaluation of dilated cardiomyopathy in the setting of normal coronary arteries,
• patients with positive cardiac enzymes without obstructive atherosclerosis on angiography,
• patients suspected of amyloidosis or other infiltrative diseases,
• hypertrophic cardiomyopathy,
• arrhythmogenic right ventricular dysplasia, or
• syncope or ventricular arrhythmia.

CMR may be used for clinical evaluation of cardiac masses, extracardiac structures, and involvement and characterization of masses in the differentiation of tumors from thrombi.

CMR may be used as a noninvasive imaging modality to diagnose patients with suspected pericardial disease. CMR can provide a comprehensive structural and functional assessment of the pericardium as well as evaluate the physiological consequences of pericardial constriction.

CMR may be used for assessing cardiac structure and function, blood flow, and cardiac and extracardiac conduits in individuals with simple and complex congenital heart disease. Specifically, CMR can be used to identify and characterize congenital heart disease, to assess the magnitude or quantify the severity of intracardiac shunts or extracardiac conduit blood flow, to evaluate the aorta, and to assess the pathological and physiologic consequences of congenital heart disease on left and right atrial and ventricular function and anatomy.

CMR may be used for assessment of LV and RV size and morphology, systolic and diastolic function, and for characterizing myocardial tissue for the purpose of understanding the etiology of LV systolic or diastolic dysfunction. The writing committee recognizes the potential capabilities of spectroscopic techniques for acquiring metabolic information of the heart when evaluating individuals with heart failure.

CMR may be used for identifying coronary artery anomalies and aneurysms and for determining coronary artery patency. In specialized centers, CMR may be uniquely useful in identifying patients with multivessel coronary artery disease without exposure to ionizing radiation or iodinated contrast medium.

The combination of CMR stress perfusion, function, and LGE allows the use of CMR as a primary form of testing for

• identifying patients with ischemic heart disease when there are resting ECG abnormalities or an inability to exercise,
• defining patients with large vessel coronary artery disease and its distribution who are candidates for interventional procedures, or
• determining patients who are appropriate candidates for interventional procedures.

Assessment of LV wall motion after low-dose dobutamine in patients with resting akinetic LV wall segments is useful for identifying patients who will develop improvement in LV systolic function after coronary arterial revascularization. The writing committee recognizes the potential advantages of spectroscopic techniques for identifying early evidence of myocardial ischemia that may or may not be evident using existing non-CMR methods. Myocardial infarction/scar LGE-CMR may be used for identifying the extent and location of myocardial necrosis in individuals suspected of having or possessing chronic or acute ischemic heart disease.

LGE-CMR may be used for identifying the extent and location of myocardial necrosis in individuals suspected of having or possessing chronic or acute ischemic heart disease.

CE-MRA may be used in patients with a strong suspicion of pulmonary embolism in whom the results of other tests are equivocal or for whom iodinated contrast material or ionizing radiation are relatively contraindicated. The writing committee agrees that data in the literature are insufficient to recommend where pulmonary CE-MRA should fit into a diagnostic pathway for pulmonary embolism.

CMR may be used for assessing left atrial structure and function in patients with atrial fibrillation. The writing committee recognizes that evolving techniques utilizing LGE may have high utility for identifying evidence of fibrotic tissue within the atrial wall or an adjoining structure. Standardization of protocols and further studies are needed to determine if CMR provides a reliable effective method for detecting thrombi in the left atrial appendage in patients with atrial fibrillation. CMR is recommended for identifying pulmonary vein anatomy prior to or after electrophysiology procedures without need for patient exposure to ionizing radiation.

CMR for PAD

• is recommended to diagnose anatomic location and degree of stenosis of PAD (Class I, Level of Evidence: A);
• should be performed with gadolinium enhancement (Class I, Level of Evidence: B); and
• is useful in selecting patients with lower extremity PAD as candidates for endovascular intervention (Class I,

Level of Evidence: A).

CMR of the extremities may be considered

• to select patients with lower extremity PAD as candidates for surgical bypass and to select the sites of surgical anastomosis

(Class IIb, Level of Evidence: B); and

• for post-revascularization (endovascular and surgical bypass) surveillance in patients with lower extremity PAD (Class

IIb, Level of Evidence: B).

Additionally, MRA of the lower extremities is appropriate for patients with claudication.

CMR may be used for defining the location and extent of carotid arterial stenoses.

CMR of thoracic aortic disease CMR may be used for defining the location and extent of aortic aneurysms, erosions, ulcers, dissections; evaluating postsurgical processes involving the aorta and surrounding structures, and aortic size blood flow and cardiac cycle–dependent changes in area.

CMR may be used for evaluating renal arterial stenoses and quantifying renal arterial blood flow. CE-MRA indicates contrast-enhanced magnetic resonance angiography; CMR, cardiovascular magnetic resonance; ECG, electrocardiogram; LGE, late gadolinium enhancement; LV, left ventricular; RV, right ventricular; MRA, magnetic resonance angiography; and PAD, peripheral arterial