Nuclear stress tests have two components to them: a treadmill stress test and scanning of the heart after injection of a radionuclide material. The material has been used in this manner safely for many years to determine the amount of blood the heart is getting under various conditions (rest and stress).

Stress tests are performed to see how the heart performs under physical stress. The heart can be stressed with exercise on a treadmill or in a few instances, a bicycle. If a person cannot exercise on a treadmill or bicycle, medications can be used to cause the heart rate to increase, simulating normal reactions of the heart to exercise.

During the stress test, you will wear EKG leads and wires while exercising so that the electrical signals of your heart can be recorded at the same time.