Cardiovascular magnetic resonance imaging, also known as cardiac MRI, is a non-invasive, no-radiation option for patients. Cardiac MRI uses a magnetic field and radio waves to get clear, sharp pictures of the heart and major blood vessels. Cardiac MRI provides detailed information on the type and severity of heart disease to determine appropriate diagnosis and specialized therapy of heart problems, such as coronary heart disease, heart valve problems cardiomyopathy (abnormal heart function) or damage from a heart attack.