Nuclear cardiology (heart perfusion imaging)

Also known as: Heart perfusion imaging, Cardiac perfusion scan, Myocardial perfusion scan, Thallium scan, Sestamibi cardiac scan, Nuclear stress test

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.