Myocardial perfusion scan

Myocardial perfusion scans use a small amount of radioactive substance to create images which show blood flow to the heart muscle.

The test can also be known as a thallium scan, MIBI scan, technetium scan or nuclear medicine scan.


What can a myocardial perfusion scan show?

The myocardial perfusion scan looks at how well your heart is pumping and the flow of blood to your heart muscle. Your doctors may refer you for other tests if they think your coronary arteries are narrowing as a stent or bypass operation may be recommended.

What happens in the MPS test?

You will have a small amount of radioactive substance injected into your blood so that blood flow can be detected.

A camera will be positioned close to your chest to take pictures of different parts of your heart, similar to an x-ray.

The scan is usually in two parts – stress and rest – so that doctors can see the effects of stress (exercise) on your heart.

For the stress element, before you are injected with the tracer you will be asked to exercise on a bike or treadmill. If you are unable to exercise you may be given a medicine instead which increases your heart rate. The camera takes pictures of your heart while you are exercising and your heart rate and blood pressure will be closely monitored throughout.

You will then have a break of about an hour, in which you will be asked to drink plenty to clear the radiation from your system. You will then go back for the rest part of the scan, which involves the same injection and camera, although this time you will just lie on the bed while the images are taken.

How long will the scan take?

Overall the appointment takes about 4 hours as there is some waiting around in-between the two parts of the test. Sometimes the scans are taken over two days and in this case they will take around one to two hours each time. The actual scan usually only takes about 20 minutes.

Is the scan safe?

You will be exposed to some radiation during the test; however it is a small amount and is considered safe. There are usually no side effects or complications from a myocardial perfusion scan.


  • If you are pregnant or think you might be, or are breastfeeding, tell your doctor as you might not be able to have the scan.

Want to find out more?

Tests booklet

Tests for heart conditions booklet

This booklet describes the special tests that are commonly used to help diagnose heart diseases.

Some of the tests are also used to assess the current condition of people who have already been diagnosed with heart disease.


 Download tests for heart conditions