Nuclear stress test

A nuclear stress test measures blood flow to your heart at rest and while your heart is working harder as a result of exertion or medication. The test provides images that can show areas of low blood flow through the heart and damaged heart muscle.

The test usually involves taking two sets of images of your heart — one while you're at rest and another after you heart is stressed, either by exercise or medication.

You may be given a nuclear stress test, which involves injecting a radioactive dye into your bloodstream, if your doctor suspects you have coronary artery disease or if a routine stress test didn't pinpoint the cause of symptoms such as chest pain or shortness of breath. A nuclear stress test may also be used to guide your treatment if you've been diagnosed with a heart condition.

Why it's done Risks How you prepare What you can expect Results

Your doctor may recommend a nuclear stress test to:

  • Diagnose coronary artery disease. Your coronary arteries are the major blood vessels that supply your heart with blood, oxygen and nutrients. Coronary artery disease develops when these arteries become damaged or diseased — usually due to a buildup of deposits called plaques.

    If you have symptoms that might indicate coronary artery disease, such as shortness of breath or chest pains, a nuclear stress test can help determine if you have coronary artery disease.

  • See the size and shape of your heart. The images from a nuclear stress test can show your doctor if your heart is enlarged and can measure its pumping function (ejection fraction).
  • Guide treatment of heart disorders. If you've been diagnosed with coronary artery disease, arrhythmia or another heart condition, a nuclear stress test can help your doctor find out how well treatment is working. It may also be used to help establish the right treatment plan for you by determining how much exercise your heart can handle.

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