A nuclear stress test is performed to measure blood flow to the heart muscle at rest and after exercise. It is similar to a routine stress test, but includes the injection of a small amount of a radioactive substance into the bloodstream to provide images of low blood flow or areas of damaged heart muscle. Nuclear scans are often used to identify:

  • Causes of chest pain
  • Extent of a coronary artery blockage
  • Location and size of damage from a heart attack

In a nuclear stress test, a special camera is used to take images of the heart at rest, and then immediately following exercise. If exercise is impossible, medication may be used to increase the heart rate.