The treadmill test is a cardiology examination that allows for the indirect evaluation of blockages in the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that.
It also assesses cardiovascular condition. One could say it is the “gateway” test for determining the presence or absence of blockages in the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that.
Effort Impossible
Sometimes it is impossible to use the treadmill test in cases where the patient is unable to walk or does so with the aid of a mechanical support such as a cane, walker, or rollator.
For others, the effort is insufficient to increase the heart rate enough to obtain a conclusive result.
Alternative to the Treadmill Test
“Persantine myocardial scintigraphy,” or “MIBI persantine,” is performed on patients who are unable to adequately perform a treadmill test.
The exercise test is replaced by the injection of a medication, persantine (dipyridamole).
The function of this medication is to dilate the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that that do not have significant cholesterolCholesterol is essential for the proper functioning of the human body, but it can also have harmful effects if present in excess. >> plaques.
An oxygen detective in the heart muscle
The examination is performed with the help of a radioactive tracer that “follows the traces” of oxygen in the heart muscle. This tracer binds to the active muscle cells of the heart when it is introduced into the bloodstream. It remains fixed for a short period, allowing time to take pictures using a device that records myocardial radioactivity.
What We See
Its usefulness
This screening test helps determine whether chest pain or other suspicious symptoms are of cardiac origin.
It is also useful for monitoring the progress of a patient known to have stable coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that disease, meaning they have stable atheromatous plaques in their coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that.
The test does not allow visualization of the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that themselves or determine the percentage of blockage in these arteries. However, it helps assess the impact of arterial blockages on the oxygen supply to the heart muscle.
An indirect way to assess coronary artery function
This examination helps determine, indirectly, if there are significant obstructions in the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that. In other words, it checks if cholesterolCholesterol is essential for the proper functioning of the human body, but it can also have harmful effects if present in excess. >> plaques are large enough to limit the distribution of oxygen to the heart muscle.
Need an appointment
An appointment is required for this examination.
An easy test, but with specific preparation requirements
Myocardial perfusion imaging is an easy examination.
There is a specific preparation to follow for this test. The instructions are explained when the appointment is scheduled. Some hospitals send them by mail or email along with a general questionnaire.
Failure to adhere to this specific preparation will result in the cancellation of your test.
The instructions;
- You will need to bring an up-to-date list of the medications you are taking, as these will be reviewed before starting the examination.
- You must fast (no food or drink, except water) for at least 3 hours before your appointment.
- Stop taking any over-the-counter medications (not prescribed by your doctor) 48 hours before your appointment
- Continue taking the medications prescribed by your doctor, unless otherwise instructed. You may be asked not to take your morning doses. Follow the instructions given by the nuclear medicine department.
- The day before and the day of your appointment, do not consume any form of caffeine:
-coffee, tea, even decaffeinated coffee
-soft drinks or energy drinks (e.g., Red Bull)
-chocolate (e.g., cookies, cakes, puddings, chocolate milk, etc.).
- Certain medications containing theophylline, the antidote to persantine, cannot be taken in the days leading up to the test. However, do not stop these medications without your doctor’s advice.
Your pulmonary condition may not allow for the persantine test (e.g., significant asthma, severe COPD, or other medical conditions). This will be reviewed by the supervising physician.
Possible side effects
The tracer has no side effects, except for a low level of radioactivity that persists for a few hours. This is harmless to those around you.
Persantine can cause certain side effects that are short-lived since an antidote is given at the end of the test. The most common unpleasant effects are headaches, dizziness, or nausea.
How is the examination conducted?
The examination consists of two phases: a resting phase and an exercise phase.
According to the protocol at your hospital, both phases may be conducted on the same day or over two days. This important information will be provided to you in advance.
If the examination is conducted on the same day, plan to spend 3 to 4 hours at the hospital.
PHASE 1: INJECTION AT REST
The reception
The nuclear medicine reception welcomes you and asks for your requisition, if they do not already have it.
Usual verifications
The nuclear medicine technologist verifies with you if your preparation is adequate and if your questionnaire has been properly filled out in advance.
Undress the Upper Body
You will be asked to undress the upper part of your body and put on a hospital gown.
Plastic catheter in a vein
A catheter is placed in a vein in your arm. It is a small plastic tube that remains in place throughout the examination and allows for the injection of the radioactive tracer.
Injection of Tracer at Rest
At this point, you receive an injection of a slightly radioactive substance.
This injection of the radioactive tracer, which “follows the traces” of oxygen in the heart muscle, is used to assess the oxygenation of the heart at rest.
Waiting Period
After the injection, you will return to the waiting room because a period is necessary to allow the radioactive tracer to circulate and bind to the heart muscle cells.
During this time, if the delay is short, you will need to remain fasting. However, if the delay is long, you will be allowed a light snack. It is important to follow the instructions given to you in this regard
Taking the images of your heart
To capture these images, you will lie down on an examination table, and several electrodes (small sensors for the electrical activity of your heart) will be placed on your chest to record your heart rate. A camera will rotate around your chest for about 15 minutes. You will need to remain still for the entire duration of the image capture.
Afterward, you will return to the waiting room so that the technologist can ensure the technical quality of the images before proceeding to the next step.
It may sometimes be necessary to retake these images (about 15% of the time). This can be due to patient movement during the image capture or because the heart is not optimally visible.
You may be asked to drink a little water or consume some full-fat milk and walk around before taking this second set of images.
It is important to know the appearance of your heart at rest. For example, if you have had a heart attack before, the images of the heart at rest will show the area where oxygenation is reduced or absent.
STEP 2: PERSANTINE INJECTION
To perform the second phase of the test, you will return to the examination room.
You will lie down on a bed for the placement of electrodes. These sensors, securely attached to your skin, record the electrical activity of your heart throughout the examination.
The technologist will explain the procedure for this second phase.
For a better electrical contact
Keratin on our skin can diminish the amplitude of the heart’s electrical signals. To help better capture this electricity, the skin will be lightly abraded with a small piece of sandpaper.
ECG and blood pressure measurement
Ten electrodes will be attached to your chest, along with a bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood pressure cuff on the arm opposite the catheter.
An ECG will be performed. Your bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood pressure and heart rate will be measured.
A doctor will review your information
Depending on your health condition and your responses to the questionnaire you filled out earlier, the doctor may ask you additional questions and conduct a brief examination of your heart and lungs.
Injection of the Substance that Replaces the Treadmill
The test begins with the injection of persantine (dipyridamole) into a vein in your arm over a period of 4 minutes.
Persantine is a vasodilator, meaning it dilates the arteries.
This substance is administered to simulate exertion on your heart.
During this entire phase of the test, your bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood pressure and heart rate are monitored and recorded, and electrocardiograms (ECGs) are taken.
Injection of the Marker for the Simulated Effort Phase
Between 6 and 7 minutes after the start of this injection, the mildly radioactive tracer, which allows for imaging of your heart, is injected again.
Injection of the Antidote to Counteract the Effects of Persantine
Two to 3 minutes later, a third substance is frequently injected. This substance is called aminophylline, which is the antidote to persantine.
Aminophylline blocks the effect of persantine, thereby stopping its action and alleviating any possible unpleasant effects caused by persantine.
Some patients may experience chest pain similar to that felt during exertion, while others may feel shortness of breath.
Usually, these effects disappear with the injection of the antidote. Additional doses of aminophylline can be administered if necessary.
Overall, this phase takes about 20 minutes.
Second Waiting Period
When this phase is complete, another waiting period begins, which typically lasts 1 hour. You will be directed to the nuclear medicine department for image acquisition.
During this waiting time, you may be offered a light meal.
It is important not to have a heavy meal, as a full stomach can obstruct the view of the heart. It is crucial to follow the instructions you are given carefully.
Taking the images of your heart Representing Exercise
After the waiting period, you will be called in for the second image acquisition.
Just like the first time, a camera will rotate around your chest for about 15 minutes.
Once these images are obtained, you will return to the waiting room to allow the technologist to ensure the quality of the images before you leave.
The images obtained after the injection of the MIBI persantine will be compared to those taken at rest. If there is no difference between the two phases, the test will be considered negative for significant coronary obstructions.
If a region of decreased perfusion is observed only on the persantine images, while the rest images show normal perfusion, this could indicate a lack of oxygen in a region of your heart during exertion. Depending on the extent and/or severity of the difference between the two sets of images, further tests may be necessary.
Your cardiologist will discuss this possibility with you.
And that's it
After this second set of images, you can get dressed and leave.
Imperfect Test
The results are sent to your doctor
You may ask for an additional copy of the report for another doctor
Vous pouvez demander qu’une copie du résultat soit envoyée à un autre médecin. Il suffit simplement de fournir son nom et ses coordonnées au personnel. Vous pouvez le faire au début ou à la fin de votre examen.
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