What is cardiac magnetic resonance imaging (MRI)?

Magnetic resonance imaging (MRI) is a safe, noninvasive test that creates detailed pictures of your organs and tissues. "Noninvasive" means that no surgery is done and no instruments are inserted into your body.

MRI uses radio waves, magnets and a computer to create pictures of your organs and tissues. Unlike computed tomography (to-MOG-ra-fee) scans (also called CT scans) and standard x rays, MRI doesn't use ionizing radiation or carry any risk of causing cancer. Cardiac MRI creates pictures of your heart as it's beating, producing both still and moving pictures of your heart and major blood vessels. Doctors use cardiac MRI to get pictures of the beating heart and to look at its structure and function. These pictures can help them decide how to treat people who have heart problems.

Cardiac MRI is a common test. It's used to diagnose and evaluate a number of diseases and conditions, including:

  • Coronary heart disease, also called coronary artery disease
  • Damage caused by a heart attack
  • Heart failure
  • Heart valve problems
  • Congenital heart defects
  • Pericarditis (a condition in which the membrane, or sac, around your heart is inflamed)
  • Cardiac tumors

Cardiac MRI can help explain results from other tests, such as x rays and CT scans. Sometimes, cardiac MRI is used to avoid the need for invasive procedures or tests that use radiation (such as x rays) or dyes containing iodine (these dyes may be harmful to people who have kidney problems).

Often during cardiac MRI, a contrast agent is injected into a vein to highlight portions of the heart or blood vessels. This contrast agent often is used for people who are allergic to the dyes used in CT scanning. People who have severe kidney or liver problems may not be able to have the contrast agent. As a result, they may have an MRI that doesn't use the substance (a noncontrast MRI).

This answer is based on source information from  the National Heart, Lung and Blood Institute.

Cardiac magnetic resonance imaging is a non-invasive cardiovascular diagnostic procedure. It does not utilize any x-rays or an ionizing radiation and therefore it is very safe, at least in individuals who do not have any metallic objects in their bodies. We use the influence of a magnetic field to generate the images within the heart. Cardiac magnetic resonance is an excellent test for the evaluation of the heart muscle, the function of the heart muscle, the strength of the contraction of the heart muscle and even the blood flow to the heart can be evaluated through stress testing. We can also evaluate the valves, all the chambers, all the great vessels in the heart. In addition, cardiac magnetic resonance imaging is excellent to evaluate certain communications to the heart such as an atrial septal defect, a ventricular septal defect and other abnormal communications. Once again, cardiac MRI is very safe in those subjects who do not have any metallic objects in their body.

Dr. Abdul J. Tajik, MD
Cardiologist (Heart Specialist)

Cardiac magnetic resonance imaging (MRI) uses magnetic fields and radio waves to create pictures of your heart and blood vessels. This test provides additional information on the heart and excellent pictures of the aorta and other blood vessels, allowing for specific measurements of the blood vessels. MRI cannot be used if you have any implanted metal in your body. If you experience claustrophobia (fear of being closed in), you may have trouble completing this test because you must lie in a small tube during the test. However, your healthcare provider may be able to give you a mild sedative prior to the test so it can be completed without difficulty.

Dr. Furqan H. Tejani, MD
Cardiologist (Heart Specialist)

Cardiac magnetic resonance imaging looks at the structure and function, that is it looks at what the heart looks like and how it is working without opening the chest. Our body has an abundance of water; water is made up of two hydrogen atoms and one oxygen atom. Magnetic resonance imaging in the most simplistic terms has the ability to tickle the hydrogen atoms, with the magnet and capture that motion with antennae called coils. This creates superb pictures of inside of human body without using any radiation.

A cardiac MRI (cMRI) is a scan that provides pictures of the heart and blood vessels inside the body using a magnetic field and pulses of radio wave energy. Unlike a CT scan, it does not use x-ray radiation. The cMRI generates images of the heart and blood vessels, which can help your doctor assess the heart’s structure and function. In addition to providing information on anatomy, cardiac MRI can also provide information on blood flow through the heart and vessels, function of heart valves, blood supply to the heart muscle and if scars have formed within the heart muscle. Some kinds of stress testing can be performed with a cMRI as well. A cMRI scan takes longer to perform than a cardiac CT scan.

A cardiac magnetic resonance imaging (MRI) test uses powerful magnets to create pictures of your heart and coronary arteries. During this test, you're placed in a chamber surrounded by a magnetic field. In response to the magnetic force, the atoms that make up your body's tissues produce weak signals. A computer magnifies and records these signals. They can then be used to create cross-section views ("slices") of your heart as well as three-dimensional images. These can be still or motion pictures.

A cardiac MRI test can reveal the structure and size of your heart chambers, wall and valves. It can also be used to show blood flow to and through your heart and to measure your ejection fraction. A cardiac MRI can help your healthcare providers determine the extent of heart muscle damage (as from a heart attack), assess blood flow problems and detect leaking in the heart's chambers and valves.

Cardiac magnetic resonance imaging (CMR) is a diagnostic procedure that uses a combination of a large magnet, radiofrequencies, and a computer to process detailed cardiovascular images. This non-invasive, safe method scans the body to produce information of the hearts anatomy and its arteries including the aorta and the pulmonary artery.

Cardiac MRI is able to display moving images of the heart as it is beating. This innovative procedure enables the physician to detect abnormalities in the hearts chambers, irregularities in the flow of blood through the heart, and abnormalities of the cardiovascular system. This may include cardiac tumors, disease of the cardiac valves (aortic, mitral, pulmonic and tricuspid valves), cardiac hypertrophy (enlarged and thickened heart), and cardiovascular abnormalities in the chest.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.