Myocardial Rest/Stress Study
The following information is for patients undergoing Myocardial Perfusion Imaging (Rest/Stress Study).
What is Coronary Artery Disease?
Coronary artery disease (CAD) is caused by inadequate blood supply to the heart, usually caused by blocked arteries.
What is a Myocardial Perfusion Imaging stress test?
Myocardial Perfusion Imaging stress tests are usually done in a nuclear medicine department. The test may be performed on an outpatient or an inpatient basis. The test involves an injection of a small amount of radioactive material which circulates in the bloodstream and shows if your heart muscle is receiving adequate blood supply under rest or stress conditions. The radioactive injection is called Sestamibi.
Any stress procedure may have some risks and you should consult with your physician regarding the risks and benefits of this procedure. The test and materials are used routinely world wide, under physician supervision, for myocardial imaging. The injection is not a “dye”, and there should be no side effects from the injection.
The test consists of two parts, at rest and after exercising. The test may be performed over two days or on the same day. The first part of the test is done whilst you are at rest.
Initially you will be asked to lie down on a trolley and rest for a period of 15-20 minutes. A cannula will then be placed in a vein in your arm to allow for ease of injection. The resting dose of Sestamibi is then injected through the cannula.
The resting images will be performed approximately 45 minutes after the injection.
The images are performed whilst you are lying on a scanning bed by a special camera that is able to trace the distribution of Sestamibi in your heart. The camera will rotate above your chest while the pictures are being taken,this will take about 25 minutes. You may breathe normally while the pictures are being taken. It is very important that you hold as still as possible while the camera takes the pictures of your heart. You will not receive any radiation from the camera.
The exercise part of the test is usually done using an exercise bicycle. As in a regular stress test, ECG electrodes will be attached to your chest. This will allow the physician to monitor your heart rate before, during, and after exercise. Exercising begins slowly, and approximately every 2 minutes the pace will gradually increase. As you exercise,your heart rate and blood pressure will change. This is normal and remember you are being closely monitored during the examination. At the peak of your exercise the physician will inject the Sestamibi into the cannula, and you will be asked to continue exercising for an additional minute afterwards. About 1 hour after the stress test finishes another set of pictures will be taken of your heart , only this time they will show how your heart performed during the stress test. The cannula will be removed when the test is completed.
The total time for the test is four to five hours.
Some people, due to a variety of disabilities, are unable to exercise adequately enough on a bicycle to achieve a diagnostic test result. In these cases the physician will decide on a alternative course of action for your test (rubber band arm exercise is supine position, or stress using special medication).
You should wear loose comfortable clothing,and shoes appropriate for walking. You must avoid caffeine containing beverages for at least 24 hrs. before the test. Instructions with regard to your medications will be given to you, please bring all your medications with you on the day of your test.