Cardiac magnetic resonance imaging (cardiac MRI or CMR) produces detailed images of the beating heart. The test can help doctors study the structure and function of heart muscle, find the cause of a patient's heart failure or identify tissue damage due to a heart attack.

At the University of Chicago Medicine Heart and Vascular Imaging Center, our patients have access to the latest MRI technology and the advanced expertise of our cardiologists who interpret the MRI results. Our physicians have experience safely performing MRI tests on patients with implanted defibrillators or pacemakers.

Cardiac MRI can show if heart muscle is alive or dead. It’s the most accurate test for calculating the patient’s ejection fraction, a measurement of the percentage of blood pumped out of the heart each time it contracts.

The noninvasive test does not use X-rays or radiation, but rather relies upon a large magnet, radio waves and a computer to create a series of images of the heart and its surrounding blood vessels. Some cardiac MRI patients will receive an injection of a contrast medium or dye through a vein before the scan to improve the ability of the MRI machine to capture more detailed images of tissues.

Cardiac MRI also is used to predict how the heart will respond to treatments for coronary artery disease, such as coronary artery bypass surgery or angioplasty.