A cardiac perfusion scan measures the amount of blood in your heart
muscle at rest and during exercise. It is often done to find out what may be
causing chest pain. It may be done after a
heart attack to see if areas of the heart are not
getting enough blood or to find out how much heart muscle has been damaged from
the heart attack.
During the scan, a camera takes pictures of the heart after a
special test medicine (radioactive tracer) is injected into a
vein in the arm. The tracer travels through the blood and into the heart
muscle. As the tracer moves through the heart muscle, areas that have good
blood flow absorb the tracer. Areas that do not absorb tracer may not be
getting enough blood or may have been damaged by a heart attack.
Two sets of pictures may be made during a cardiac perfusion scan.
One set is taken while you are resting. Another set is taken after your heart
has been stressed, either by exercise or after you have been given a medicine.
The resting pictures are then compared with the stress images.
This test is also known by other names including myocardial perfusion scan, myocardial perfusion imaging, thallium scan, sestamibi cardiac scan, and nuclear stress test.
Why It Is Done
A cardiac perfusion scan is done to:
- Find the cause of unexplained chest pain or
chest pain brought on by exercise.
- Check for the location and
amount of damage caused by a heart attack.
coronary artery disease (CAD).
- Help make
treatment decisions for a person with CAD.
- Check to see that the heart is getting enough blood after heart
surgery or angioplasty.
- Identify a
congenital heart defect and determine how serious it
is. These scans may also be done following surgery to correct a congenital
How To Prepare
Before a cardiac perfusion, tell your doctor if you:
- Are taking any medicines, including
erection-enhancing medicines (such as Cialis, Levitra, or Viagra). You may need
to take nitroglycerin during this test, which can cause a serious reaction if
you have taken an erection-enhancing medicine within the previous 48 hours. Ask
your doctor whether you need to stop taking any of your other medicines before
- Are allergic to any medicines or
- Are or might be pregnant.
breast-feeding. Use formula and throw out your breast milk for 1 to 2 days
after the scan.
Do not eat or drink for at least 3 hours before a cardiac perfusion
scan. If you are having a stress scan, avoid alcohol, tobacco, caffeinated
beverages, and nonprescription medicines for at least 24 hours before the test.
Wear comfortable shoes and loose shorts or pants suitable for
exercise. Remove all jewelry before the test.
Talk to your doctor about any concerns you have regarding the need
for the test, its risks, how it will be done, or what the results may mean.
To help you understand the importance of this test, fill out the
medical test information form(What is a PDF document?).