Nuclear Cardiology Tests at Mission Heritage Medical Group

A nuclear stress test helps measure blood flow to your heart muscle at rest and during stress. It is similar to a routine exercise stress test but with images in addition to electrocardiograms.

During a nuclear stress test, a radioactive substance is injected into your bloodstream. This substance mixes with your blood and travels to your heart. A special camera or scanner which detects the radioactive material in your heart creates images of your heart muscle. The two most common tests are:

• Myocardial perfusion scan. During this procedure, you exercise on a treadmill. When you reach your maximum heart rate, you're given the injection. Images are made of your heart shortly after exercise and also a few hours later. This test shows how well blood flows into the heart muscle and can detect narrowing of the coronary arteries.
• Multigated acquisition (MUGA) scan. In this test, you receive the injection before exercising. Images are made of your heart before and after exercise. A MUGA scan shows the motion of the heart and how well it pumps out blood.
• If you're unable to exercise, you may be injected with a medication that increases blood flow to your heart muscle simulating exercise for the test.