
Cardiac MRI
Cardiac MRI uses a powerful magnetic field, radio waves and a computer to produce detailed pictures of the structures within and around the heart.
Are Cardiac MRI's safe?
Yes, which is particularly important as some patients, such as those with complex congenital heart disease, need multiple scans over time.
A cardiac MRI scan is a non-invasive test which involves using and MRI scanner to create a clear picture of the inside of the heart.
It doesn't use any radiation just magnetic and radio waves to create the picture. An MRI scan is a test used by doctors to create a detailed picture of internal organs. These can be done for all sorts of body parts.
What does a cardiac MRI show?
Doctors use the cardiac MRI to show them the heart's structure (including the muscles, chambers and even down to the small valves in the heart). From this, in conjunction with other tests, they can check how well the heart is functioning. A cardiac MRI can be very useful for assessing the presence of:
- Congenital heart disease
- Ageing and wear of the valves
- Heart damage following a heart attack
- Heart health
- Blood flow to the heart
What happens during the MRI scan?
At the start you will be asked to lie on a bed which moves inside a tunnel-like scanner (the scanner is open at both ends, just like a short tunnel). During the scan you will be asked to lie still. The MRI scan could take up to 1 hour but if you feel uneasy or need to talk to the operator (called a radiographer) there is a buzzer to press.
The scanner itself can be quite noise so you will be offered ear plugs or headphones to listen to music whilst the scan takes place.
For some scans the doctor will use a dye (called contrast) injected into a vein on the arm so that the images of the blood flow to the heart can be seen more clearly.
The test is pain free but can be uncomfortable if you are claustrophobic - so it's worth mentioning this beforehand if you are.
When do you get the results?
You don't need to stay in hospital over night, you will be able to go home after the scan. The results of the scan will usually be given to you in a follow up appointment within a few days with you cardiologist, who suggested the scan in the first place.
Can everyone have a cardiac MRI scan?
Individuals with a pacemaker or implantable cardiac defibrillator should make sure the person performing the scan is aware. Whilst most modern devices like this are MRI suitable it very important to check beforehand.
Individuals with inner ear implants or surgical foreign body (like a metal clip in the eye or brain) cannot have an MRI. This is because the scanner uses strong magnets which may cause the metal parts to move.
Do I need to do anything to prepare?
- Tell your doctor if you have any metal implants.
- Tell your doctor if you are pregnant.
- Usually you can eat normally before the test.
If you have any questions it is always best to just ask one of our friendly team.

Healthy Living
Keeping your heart healthy involves maintaining an active lifestyle and identifying any potentially dangerous heart problems before they become more severe.