Stress Tests
Reviewed
Stress tests show how well your heart works when it's pumping hard. They check blood flow in your heart, your blood pressure, the rate and rhythm of your heartbeat, and the strength of the electrical signals that control your heartbeat. Some stress tests also take pictures of your heart at rest and when it's working hard. They are most often used to find the cause of symptoms that may be from a heart problem and can help diagnose certain heart conditions.
Preparation and collection
Wear comfortable shoes and clothing for exercise. You'll usually need to fast (not eat or drink) and stop smoking for at least a few hours before the test. You may need to avoid drinks with caffeine, such as coffee, tea, and colas, for a longer period of time. If you take medicines or supplements, ask your provider if you should take them as usual. Don't stop taking any medicine unless your provider tells you to. If your test uses MRI, tell your provider about any metal you have in your body.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- Stress tests are usually safe, but you will be closely watched during the test. If a problem develops, you'll be treated quickly.
- Medicines that make your heart work harder sometimes cause symptoms such as chest pain, dizziness, or nausea.
- An IV may bruise your arm.
- The tracers and dyes used in nuclear and MRI stress tests may cause an allergic reaction, but this is rare.
- If you are or could become pregnant or are breastfeeding, talk with your provider before you have these tests.
What to do next
Your provider will explain what condition you may have. You may need more tests to find out how serious your condition is.