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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Participate in NHLBI Clinical Trials

The National Heart, Lung, and Blood Institute (NHLBI) leads or sponsors many studies aimed at preventing, diagnosing, and treating heart, lung, blood, and sleep disorders.

Are you at risk of unstable angina?

This study aims to recruit people in an emergency room for angina who have low or moderate troponin levels in the blood. Troponin is a sign of damage to the heart. This study will assess whether cardiac magnetic resonance imaging (MRI) is as effective as invasive procedures, such as angiography or coronary artery bypass grafting, in helping health providers make decisions about treatment for this group of patients. To participate in this study, you must be at least 21 years old and in an emergency room with chest pain and slightly elevated troponin levels. This study is located in Royal Oak, Michigan; Jackson, Mississippi; Winston-Salem, North Carolina; and Columbus, Ohio.

Are you an adult who wants to help improve MRI scans for assessing blood vessels of the heart?

This study is looking for ways to improve a special type of magnetic resonance imaging (MRI) scan to evaluate obstructive and nonobstructive coronary artery disease. To participate in this study, you must be healthy or have heart disease and be at least 18 years old. This study is located in Bethesda, Maryland.

Has your doctor recommended right heart cardiac catheterization for you?

This study is investigating new magnetic resonance imaging (MRI) techniques that use a guidewire to help position a heart catheter within the heart. MRI fluoroscopy shows pictures of the heart so that doctors can watch while they work. Using the guidewire during MRI may improve the procedure of heart catheterization. To participate in this study, you must be at least 18 years old, and your doctor must have recommended right heart catheterization for you. This study is located in Bethesda, Maryland.

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