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 given through an IV. 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.