Cardiac magnetic resonance imaging

Cardiac magnetic resonance imaging (cardiac MRI, CMR), also known as cardiovascular MRI, is a magnetic resonance imaging (MRI) technology used for non-invasive assessment of the function and structure of the cardiovascular system. Conditions in which it is performed include congenital heart disease, cardiomyopathies and valvular heart disease, diseases of the aorta such as dissection, aneurysm and coarctation, coronary heart disease. It can also be used to look at pulmonary veins. Patient information may be found here. It is contraindicated if there are some implanted metal or electronic devices such as some intracerebral clips or claustrophobia. These can be looked up to see if they are MRI conditional. For pacemaker or defibrillator patients, almost all can be scanned but special protocols are needed. Conventional MRI sequences are adapted for cardiac imaging by using ECG gating and high temporal resolution protocols. The development of cardiac MRI is an active field of research and continues to see a rapid expansion of new and emerging techniques. Cardiovascular MRI is complementary to other imaging techniques, such as echocardiography, cardiac CT, and nuclear medicine. The technique has a key role in evidence-based diagnosis and treatment of cardiovascular disease. Its applications include assessment of myocardial ischemia and viability, cardiomyopathies, myocarditis, iron overload, vascular diseases, and congenital heart disease. It is the reference standard for the assessment of cardiac structure and function, and is valuable for diagnosis and surgical planning in complex congenital heart disease. Combined with vasodilator stress, it has a role in detecting and characterizing myocardial ischemia due to disease affecting the epicardial vessels and microvasculature. Late gadolinium enhancement (LGE) and T1 mapping allow infarction and fibrosis to be identified for characterizing cardiomyopathy and assessing viability. Magnetic resonance angiography may be performed with or without contrast medium and is used to assess congenital or acquired abnormalities of the coronary arteries and great vessels.