Sestamibi Scan - "Mibi"

A sestamibi (MIBI) scan is a test that measures the amount of blood being supplied to your heart.


What is a sestamibi scan?

A sestamibi (MIBI) scan measures the amount of blood being supplied to your heart. The scan is done in two parts:

  1. At rest - sitting and breathing normally
  2. After a chemical or physical stress test - when your heart is beating faster after exercising on a treadmill or exercise bike.

Why do I need a sestamibi scan?

Your doctor may recommend a sestamibi scan in order to:

  • Determine the cause of chest pain
  • Find out if any areas of your heart are damaged or not getting enough blood if you’ve recently had a heart attack
  • Determine the best treatment for you if you have coronary artery disease

What are the risks of having a sestamibi scan?

The sestamibi scan uses low levels of radiation and is usually very safe. Sometimes, the medicine given to increase your heart rate during the stress test can cause headaches, nausea, dizziness and flushing - and these symptoms can last for a few minutes. Also, exercising during the stress test can cause breathlessness, dizziness and tiredness. Remember, a nurse will be with you throughout the test to ensure your safety. If you’re experiencing severe symptoms, your test will be stopped.

How do I prepare for a sestamibi scan?

There are a few things you’ll need to do to prepare for your sestamibi scan, including:

  • Avoid caffeine for 24 hours before the test - caffeine may reduce the quality of the scan results (caffeine is in tea, coffee, cola and chocolate
  • Fast (not eat) for 4 hours before the test - but you can drink water
  • Talk to your doctor about your medications - see if there’s any medicine that you need to stop taking
  • Dress comfortably - you’ll be exercising in the stress test, so remember to wear suitable shoes and clothes

What happens during a sestamibi scan?

The scan is usually done in the nuclear medicine department of your hospital. During the resting scan:

  • You’ll be asked to wear a hospital gown
  • Sticky dots will be put on your chest to monitor your heart rate
  • A cannula will be put in (usually in your arm)
  • A small amount of radioactive solution (sestamibi) will be given through the cannula
  • You’ll be asked to lie on the scan table
  • A camera will be above your chest taking pictures of your heart

During the stress scan:

  • You’ll be asked to perform a stress test
  • If you are unable to exercise, you’ll be given medicine to speed up your heart rate
  • When your heart rate reaches the limit for your age, a small dose of sestamibi will be given in the cannula
  • You’ll then have more pictures taken and will need to lie still
  • It usually takes 5-6 hours to complete both parts of a sestamibi scan.

What happens after a sestamibi scan?

After your sestamibi scan, your doctor will analyse and compare the pictures of your heart. A normal test shows even distribution of sestamibi. An abnormal result means that some areas of the heart are not getting enough blood. After reviewing your pictures, your doctor will talk to you about the results, potential treatments and your options.