Learn about MRI
What is MRI?
Magnetic resonance imaging (MRI) is a noninvasive test that uses a magnetic field and radiofrequency waves to create detailed pictures of organs and structures inside your body. It can be used to examine your heart and blood vessels and to identify areas of the brain affected by stroke. Magnetic resonance imaging is also sometimes called nuclear magnetic resonance (NMR) imaging
Quick facts
MRI uses a powerful magnetic field, radiofrequency waves, and a computer to create detailed cross-sectional (2-dimensional) and 3-dimensional images of the inside of your body without using ionizing radiation (like X-rays, computed tomography, or nuclear imaging).
The test can show your heart’s structure (muscle, valves, and chambers) and how well blood flows through your heart and major vessels.
MRI of the heart lets your doctor see if your heart is damaged from a heart attack, or if there is a lack of blood flow to the heart muscle because of narrowed or blocked arteries.
MRI of the brain is used to diagnose stroke, aneurysm, and other brain abnormalities.
MRI of the pelvis and legs helps to diagnose peripheral artery disease (PAD).
MRI scans for heart
An MRI can help your doctor diagnose many different heart conditions, including:
- Tissue damage from a heart attack
- Reduced blood flow in the heart muscle to help determine whether heart artery blockages are the cause of your chest pain (angina)
- Problems in the aorta—the heart’s main artery—such as a tear, aneurysm (bulge), or narrowing
- Diseases of the pericardium (outer lining of the heart muscle) such as constrictive pericarditis
- Heart muscle diseases, such as heart failure or enlargement of the heart, and abnormal growths such as cancerous tumors
- Heart valve disorders, such as regurgitation
- Congenital heart problems and the success of surgical repair
MRI may be used instead of other tests that use ionizing radiation or iodine-containing contrast dyes, or both, such as X-ray, angiograms, and computed tomography (CT) scans. Using MRI to look at blood vessels and how blood flows through them is called magnetic resonance angiography (MRA).
Unlike a traditional X-ray angiogram, this procedure doesn’t require inserting a catheter into your arteries. MRI techniques can also be used to measure heart function or how much blood the left ventricle can pump out to the body.