A nuclear stress test is an imaging test that shows how blood goes to the heart at rest and during exercise. It uses a small amount of radioactive material, called a tracer or radiotracer. The substance is given by IV. An imaging machine takes pictures of how the tracer moves through the heart arteries. This helps find areas of poor blood flow or damage in the heart.

A nuclear stress test is often done to:

Diagnose coronary artery disease. The coronary arteries are the major blood vessels that supply the heart with blood, oxygen and nutrients. Coronary artery disease develops when these arteries are damaged or diseased. A nuclear stress test can diagnose coronary artery disease and show how severe the condition is.

Create a treatment plan. If you have coronary artery disease, a nuclear stress test can tell your health care provider how well treatment is working. The test also shows how much exercise your heart can handle. This information helps your provider choose the best treatment for you.