Explore Cardiac MRI
Cardiac MRI takes place in a hospital or medical imaging facility. A radiologist or other doctor who has special training in medical imaging oversees MRI testing.
Cardiac MRI usually takes 30 to 90 minutes, depending on how many pictures are needed. The test may take less time with some newer MRI machines.
The MRI machine will be located in a special room that prevents radio waves from disrupting the machine. It also prevents the MRI machine's strong magnetic fields from disrupting other equipment.
Traditional MRI machines look like long, narrow tunnels. Newer MRI machines (called short-bore systems) are shorter, wider, and don't completely surround you. Some newer machines are open on all sides. Your doctor will help decide which type of machine is best for you.
Cardiac MRI is painless and harmless. You'll lie on your back on a sliding table that goes inside the tunnel-like machine.
The MRI technician will control the machine from the next room. He or she will be able to see you through a glass window and talk to you through a speaker. Tell the technician if you have a hearing problem.
The MRI machine makes loud humming, tapping, and buzzing noises. Some facilities let you wear earplugs or listen to music during the test.
You will need to remain very still during the MRI. Any movement can blur the pictures. If you're unable to lie still, you may be given medicine to help you relax.
The technician might ask you to hold your breath for 10 to 15 seconds at a time while he or she takes pictures of your heart. Researchers are studying ways that will allow someone having a cardiac MRI to breathe freely during the exam, while achieving the same image quality.
A contrast agent, such as gadolinium, might be used to highlight your blood vessels or heart in the pictures. The substance usually is injected into a vein in your arm using a needle.
You may feel a cool sensation during the injection and discomfort when the needle is inserted. Gadolinium doesn't contain iodine, so it won't cause problems for people who are allergic to iodine.
Your cardiac MRI might include a stress test to detect blockages in your coronary arteries. If so, you'll get other medicines to increase the blood flow in your heart or to increase your heart rate.
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