What is a heart MRI?
A heart MRI is a scan of your heart in which radio waves and magnets create images without anything you can see or feel going into your body. A cardiac MRI can show the parts of your heart (including chambers, valves and muscles) and how well they are working ― including how your blood moves. These detailed, high-quality images in two or three dimensions help your healthcare provider figure out what’s wrong and make a diagnosis.
What can a heart MRI diagnose?
Your provider orders a cardiac MRI when they’re trying to diagnose a problem with your heart, such as:
- The cause of your chest pain, shortness of breath or fainting.
- An enlarged heart.
- Thickening of heart muscle.
- Heart failure.
- Heart muscle damage, inflammation, infiltration and infection.
- Heart valve disease, including leaky valves, narrowed valves and prosthetic valves.
- Heart disease.
- Abnormal iron deposition in the heart.
- A torn, narrow, dilated or inflamed aorta.
- Diseases that affect your pericardium (the tissue or sac around your heart).
- Cancer and other masses.
- Congenital heart issues you’ve had since you were born.
When is a heart MRI performed?
A heart MRI is performed to obtain a comprehensive analysis of heart structure, function and diseases. In addition to diagnostic reasons above, there are other times you may need a heart MRI, including when your provider needs to:
- Check for damage to your heart after a heart attack or areas that lack blood flow because of heart artery blockages.
- Pinpoint a location they need to treat during an ablation.
- See how much your treatment is helping your heart.
- Plan a procedure or treatment on your heart.
- Evaluate the success of a recent surgery.
- Check to see how a disorder has affected your heart since the last scan.
Who performs this procedure?
A healthcare provider working at a hospital or outpatient facility operates the MRI machine and saves the images it takes. After they help you get ready for your scan, they go to a separate part of the room that’s behind glass they can look through to see you.
How does a heart MRI work?
Unlike some other forms of imaging, a cardiac MRI doesn’t use any radiation. It uses a massive magnet and radio waves to create high-quality images of your heart on a computer.
How do I prepare for a heart MRI?
A heart MRI won’t harm you, but your healthcare provider may ask if you’re pregnant or if you have any metal inside your body. In some cases, an MRI may not be right for you. Some medical devices don’t work right or can interfere while you’re inside an MRI. Be prepared to tell your provider what kind of device you have, since certain types (like an intrauterine device or some pacemakers) aren’t safe in the MRI machine. Your healthcare provider can check their database to see which devices are safe and compatible with having an MRI.
Your provider will also ask about any allergies you have, as well as health problems and surgeries in your history.
If you get nervous or uncomfortable in tight spaces, ask your provider a few days in advance for a pill that will relax you before your cardiac MRI. You can usually pick it up at the pharmacy and take it a half hour before your MRI. Just remember that you’ll need someone to drive you to and from your cardiac MRI if you take a sedative to relax.
What to expect on the date of the heart MRI
- Take your normal medicines and eat regular meals unless your provider tells you not to.
- Don’t wear any jewelry because it will cause problems with the machine’s magnets and images. An MRI can damage jewelry, as well.
- Don’t forget to remove any piercings, glasses, hearing aids or hair barrettes that contain metal.
- Wear clothes that are comfortable and don’t have metal on them. You’ll need to change into a hospital gown if you have metal in your clothes, like the zipper on your jeans or the metal in your bra. You can keep your underwear and socks on.
You can place your clothing, jewelry and other items in a patient locker. Since you can’t take the locker key inside the MRI, your provider can put it in a safe place for you.
Sometimes, your provider may want to give you a contrast substance such as gadolinium, which can make it easier to see some details in your scans. This is different from the contrast used for other imaging like CTs. You’ll get this through an IV in your arm.
You’ll need to lie down on a long platform that will slide into the empty space in the middle of the MRI machine, which is shaped like a large doughnut standing on its side. Some MRI machines (open MRI) don’t make a complete circle around you, which can be easier for people who need or want more space around them.
Your provider may put stickers with electrocardiogram leads on your chest and a belt below your chest to collect information about your heartbeats and breathing during your cardiac MRI scan.
What to expect during the MRI heart scan
Your scans should take a half hour to an hour and a half. The machine may do several scans, with each one lasting a few minutes. Sometimes, your provider will ask you to hold your breath for part of the scan.
You’ll need to lie on your back without moving during scans. The machine is loud and may sound like an electronic video game or something pounding around you, but you’ll be able to communicate (through a microphone and headphones or intercom) with the person operating the machine. They may put a call button in your hand that you can squeeze if you need to contact the person doing the scan. You may be able to listen to music through the headphones they put on you.
What to expect after your heart MRI
Your provider will slide the table you’re on out of the MRI machine. If you had an IV, they’ll remove it. Then you can get your belongings, get back into your clothes and go home.
What are the side effects of a heart MRI?
If you took a sedative to relax, you may feel tired until the effects of the pill wear off. If not, you can return to your normal activities.
If you received contrast through an IV, you might have a metal-type taste for a little while or some bruising or irritation where the IV was put in. Rarely, people may have nausea or a headache from the contrast they got in their IV.
Results and Follow-Up
What type of results do you get and what do the results mean?
The healthcare provider who reviews the scans (usually a radiologist or cardiologist who specializes in interpreting images) will send them to the provider who ordered your cardiac MRI. Your provider may show you images at your next appointment while explaining your diagnosis.
When should I know the results of the heart MRI?
It may take a couple of days for you to get your results.
When should I call my doctor?
If you’re having symptoms of a heart problem, call your provider right away.
If you’ve had a cardiac MRI and haven’t heard from your healthcare provider in a few days, it’s a good idea to follow up on your results.
A note from Cleveland Clinic
Your healthcare provider may order a heart MRI for you so they can get a comprehensive, accurate look at your heart without doing surgery. This is a safe test with no radiation, but it’s important to lie still during your cardiac MRI scan and follow the breathing instructions. Moving makes the images blurry. Although the person operating the heart MRI machine will be across the room and behind glass, they will be able to see you and communicate with you during the entire test.
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