Nuclear Medicine Cardiac Stress Test
Why is the test done?
The cardiac stress test is used to find out if there is significant blockage of the blood supply to the heart (coronary artery disease). In this test, the doctor is looking at the heart muscle itself and the amount of radioactive material picked up (perfused) by the heart. This test gives doctors a good idea of what is going on in your heart.
What can you expect?
You will go to the UW Hospital and Clinics for the test. Use the clinics entrance and ask for help to find the Radiology check-in desk at G3/3. The cardiac stress test is done in two parts: a “rest” part and a “stress” part. It takes about 3 hours to complete.
How should you prepare for the test?
- Do not eat or drink for four hours before the exam.
- If you take insulin, you should talk to your doctor or clinic to change your dose for the day. If your drive is longer than three hours, it is okay to have a light breakfast of juice and toast before leaving home. If you use a blood sugar meter, please bring it along to the test.
- Do not have any caffeine 12 hours before the test. This includes coffee, tea chocolate, and sodas with caffeine.
- Bring pants or shorts that are easy to move in and soft-soled shoes.
- Contact your doctor with questions about any drugs you are on for your heart or blood pressure. Your doctor will have to decide whether to stop them before the test. If you were told not to take certain drugs, bring them with you, and take them after the test.
- You will be asked to sign a consent form for the exercise.
- Bring a complete list of medicines you are currently taking.
The “rest” part of the test
If you are claustrophobic and require medicine, please refer to your primary physician (PCP) for your needs. The “rest” images will be done before the stress test and will be compared with the others obtained after the stress part of the test.
For the “rest” images, a radioactive material that helps get pictures of your heart will be put in through an IV line, and pictures will be taken 15-30 minutes later. You will be asked to lie flat on a table and remain still while the pictures are being taken. The machine moves slowly around your chest while you lie still. Each picture takes between 25-30 seconds and the entire scan is done in about 15-20 minutes.
The “stress” part of the test
There are two ways the “stress” portion of the test can be done.
- If you are able to walk about five blocks without pain, your heart can be stressed by walking on a treadmill. This workout will start out easy and slowly get harder. This is known as a treadmill stress test.
- If you are not able to walk much, one of two drugs can be used to “stress” the heart. These will be given through an IV. This is known as a drug stress test.
For the stress test, small sticky pads will be placed on your chest. The contact of these pads to the skin is important to get a good signal. You may have some discomfort with the preparation of the skin for the pads. These pads will be hooked to an ECG monitor, so that your heart rate and rhythm can be watched closely throughout the test.
Your heart rate and blood pressure will be watched during the stress. Tell the person giving the test if you have any of these symptoms at any time:
- Chest or arm pain
- Shortness of breath
A radioactive material will be put in through the IV line about 1 ½ minutes before the end of the stress test. It is carried to the heart by the blood where it is taken up by the heart muscle cells. The “stress” images will be taken 30-60 minutes after your stress test. A short CT scan will also be done to define body structures. This will aid the doctors reading of your scan. The entire scan is done in 15-20 minutes.
Any further questions?
If you have any other questions or concerns, we will gladly help you with them. You can reach the Nuclear Medicine Clinic at (608) 263-1462. If you live out of the area, call 1-800-323-8942 and ask for the Nuclear Medicine Clinic.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 07/07/2011
Copyright © 07/07/2011 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#4585
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