Description of Test
You will lie down on a table. A technician will place electrodes on your chest. Your resting blood pressure and ECG readings will be taken. An IV (hollow needle and thin tube) will be placed in your arm. You will be hooked up to a heart monitor that will record your heart’s activity. Your blood pressure and heart rate will be checked often. A small amount of chemical will be injected through the IV and into your body. Depending on which chemical is used, your heart will beat faster and/or the blood vessels near your heart will open wider. An ECG may also be done at this time.
If you have chest pain, trouble breathing, dizziness, or any other symptoms, tell your doctor or technician right away. The test may need to be stopped. Changes in the ECG may also be a reason to stop the test.
If you are getting nuclear imaging, the technician will inject a mildly radioactive chemical through your IV. Thirty to sixty minutes after the chemical injection, a special camera or an MRI will be used to track the flow of the chemical through and around your heart. Images will be taken to find areas of the heart that may not be getting enough blood or are blocked. If you are getting a stress echocardiogram, an ultrasound will be taken at specific time points. The doctor will compare the pictures of your heart under stress with pictures of your heart at rest.
Your blood pressure, heart rate, and ECG will be monitored until levels return to normal. You will be able to leave after the test is done.
Your doctor may discuss some of the results on the same day as the test. It may take 2-3 days for the full results to be ready.
One or more of the following are considered a positive stress test:
- ECG changes that show low oxygen supply to the heart
- Significant blood pressure drops or rhythm changes
- You have chest pain or trouble breathing, especially if linked with ECG changes
- Stress test pictures that show areas of your heart having low blood flow or abnormal movements
A positive test may mean that you have CAD. Not everyone tests positive for it. Based on your results, your doctor may recommend more tests or care.