In this common type of scan, the radioactive isotope thallium is
injected into your vein at rest and at the end of an exercise or
pharmacologic stress test. Images are taken after each injection
that show how the blood is flowing through your heart arteries.
If the heart arteries have blockages, there is not enough blood
flow through them during stress, resulting in an abnormality on
the scan. This test can also identify regions of damage or
scarring of the heart muscle due to previous heart attack.
scarring of the heart muscle due to blocked coronary arteries or
a previous heart attack. Please click here to learn more about
thallium scans, including how to prepare and what to expect.