Cardiac MRI

Also known as Magnetic Resonance Imaging (MRI), Nuclear Magnetic Resonance
A cardiac MRI is a painless imaging test that uses radio waves, magnets, and a computer to create detailed pictures of your heart.

Cardiac MRI can provide detailed information on the type and severity of heart disease to help your doctor decide the best way to treat heart problems such as coronary heart disease, heart valve problems, pericarditis, cardiac tumors, or damage from a heart attack. Cardiac MRI can help explain results from other imaging tests such as chest x rays and chest CT scans.

Cardiac MRI may be done in a medical imaging facility or hospital. Before your procedure, a contrast dye to highlight your heart and blood vessels, may be injected into a vein in your arm. You may feel discomfort from the needle or a cool feeling as the contrast dye is injected. The MRI machine is a large, tunnel-like machine that has a table. You will lie still on the table and the table will slide into the machine. You will hear loud humming, tapping, and buzzing sounds when you are inside the machine as pictures of your heart are being taken. You will be able to hear from and talk to the technician performing the test while you are inside the machine. The technician may ask you to hold your breath for a few seconds during the test.

Cardiac MRI has few risks. In rare instances, the contrast dye may harm people who have kidney or liver disease, or it may cause an allergic reaction. Researchers are studying whether multiple contrast dye injections, defined as four or more, may cause other adverse effects. Talk to your doctor and the technicians performing the test about whether you are or could be pregnant. Let your doctor know if you are breastfeeding because the contrast dye can pass into your breast milk. If you must have the contrast dye injected, you may want to pump and save enough breast milk for one to two days after your test or you may bottle-feed your baby for that time. Tell your doctor if you have:

  • A pacemaker or other implanted device because the MRI machine can damage these devices.
  • Metal inside your body from previous surgeries because it can interfere with the MRI machine.
  • Metal on your body from piercings, jewelry, or some transdermal skin patches because they can interfere with the MRI machine or cause skin burns. Tattoos may cause a problem because older tattoo inks may contain small amounts of metal.

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