Myocardial Perfusion Imaging (MPI) or Cardiolite Stress Test
The myocardial perfusion imaging (MPI) or Cardiolite stress test is a diagnostic exam used to evaluate the extent of blood supply your heart is getting. A radioactive injection called a radiopharmaceutical or tracer will be given to you at various stages of the exam and this is needed to create the images of the heart. This tracer only highlights the extent of blood flow to your heart – it does not interfere with how your heart works or change how you feel in anyway. During the examination you will also complete a stress test – either by walking on a treadmill or for patients who cannot do this a medication called Persantine will be given to mimic the effects of physical exertion on the heart. After the procedure is completed the images will be evaluated by a cardiologist and radiologist and a report will be sent to your doctor.
What You Should Know
On the day of your cardiac stress test, please exclude caffeine products, alcohol and smoking. Caffeine products include: coffee and tea (decaffeinated and caffeinated), chocolate, cocoa, pop, energy drinks and any medication or supplements that may have caffeine. If you are taking heart or blood pressure medications, check with your physician whether you are to stop the medication before the test.
We prefer that you have consumed any caffeine products for 24 hours before your test appointment, as this may jeopardize the quality of your test. If you arrive having consumed caffeine products within the last 12 hours, your procedure will be cancelled and rescheduled to the next available routine booking date.
Certain medications, such as "beta blockers", should be discontinued for a period of time before arriving for the test (normally 48 hours). Since every patient may be having this test for a different reason, you must confirm with your physician which medicine is appropriate and safe for you to stop before arriving for your heart test, as well as how long the medicine should be stopped.
If you are scheduled for a Persantine stress test, please stop taking Theophylline at your physician's request.
- Before your visit
Please do not engage in strenuous exercise (brisk walking or jogging) on the day of your test. We need you rested. Wear loose-fitting, comfortable, short-sleeved exercise clothing (t-shirt and shorts or jogging pants) and rubber-soled shoes (running shoes). Do not wear a dress or skirt. Women should wear a bra for exercise.
You should not eat for three to four hours prior to the test; however water and juice are permitted before arriving. If you are diabetic, you may have a light snack (toast and juice) two hours prior to your test if needed to stabilize your blood sugar levels.
- After your visit
Please note that Persantine could cause headache or nausea. Download our myocardial perfusion imaging or cardiolite stress test brochure for more information.
- Care providers
There are two parts to a myocardial perfusion test. The imaging scans are performed by a medical radiation technologist (MRT) specialized in nuclear medicine and the stress testing components are carried out by a cardiology technologist. A physician will supervise your care during the stress testing component. To learn more about these health professionals see the websites for College of Medical Radiation Technologists of Ontario - About MRTs and Canadian Society of Cardiology Technologists - What Is A Cardiology Technologist
Frequently Asked Questions
- How long will the Cardiolite remain in my system?
Your body will eliminate the Cardiolite after one or two days.
- Why do I have to wait before the scan?
This allows time for the Persantine or Cardiolite to perfuse into your system.
- Why do I have to have an IV?
It is easier to inject the Cardiolite while you are walking on the treadmill if it is done through an intravenous. It prevents you from having two separate injections.
- How does the Cardiolite work?
The Cardiolite binds itself to the red blood cells and is circulated to the heart. We take pictures to show if there are any occlusions (obstructions) in blood flow to the heart.
- Why do I have to exercise with this test?
The exercise stresses the heart so we can see if there are any changes that will indicate areas sensitive to stress.
- Why do I have to sign a consent form?
There are slight risks to this test and the consent form allows you to be treated should any problems occur during the test.
- Is Cardiolite a dye?
No, Cardiolite is a radioactive isotope. It is not a dye and does not have any side effects.
- Can I travel after this test?
If you are planning on travelling outside of the country within three days of the test, please let the technologist know. They will provide you with a letter that you can present at customs (airport security, borders, etc.).