PERSANTINE STRESS ULTRASOUND
The treadmill is a cardiology exam that evaluates whether the heart receives enough oxygen during exercise.
However, for various reasons, it may be difficult or impossible for some people to walk on a treadmill and provide sufficient effort for the results of the examination be conclusive.
A substitute test may then be requested by your doctor.
This exam is called Persantine Stress Ultrasound.
What is the exam?
This exam consists of comparing the contraction of the heart at rest with its response after the injection of a product into a vein that simulates physical activity.
The results of a cardiac ultrasound allow for this.
The purpose of the exam
We want to "see" how the heart reacts to persantine which simulates an effort.
The goal may be to replace the treadmill test for people who cannot walk on one or cannot do so efficiently.
For other patients, the goal is to confirm or clarify the result of an abnormal or inconclusive treadmill test by pinpointing the region of the heart where a coronary blockage may be present.
Relatively easy examination
Although longer than a simple ultrasound, it is a relatively easy test.
Your lung condition may not be able to perform the persantine test (major asthma, significant COPD), or other medical conditions.
This will be reviewed by the doctor supervising the examination.
An appointment is necessary
You must schedule an appointment for this exam done externally.
A special preparation must be done prior to the exam.
The instructions will be explained to you when you call for your appointment. Some hospitals send them by mail et email along with a general questionnaire.
If the steps are not completed adequately prior to the exam, your test will be cancelled.
The instructions ;
· You will need to bring with you the list of medications you are taking as they will be reviewed before you start the exam.
· You must be fasting (without eating or drinking anything other than water) at least 4 hours before your appointment.
· Stop taking any medications bought on the shelves (not prescribed by your doctor) 48 hours before your appointment.
· Continue taking the medications prescribed by your doctor unless you are told otherwise. Check this point with your doctor.
· The day before and the day of your appointment, do not consume any form of caffeine;
o coffee, tea, even decaffeinated coffee
o soft drinks or energy drinks (eg Red Bull)
o chocolate (eg cookies, cakes, pudding, chocolate milk, etc.).
Regarding your medications
Some drugs, containing theophylline, the antidote of persantin, can not be taken in the days preceding the examination.
However, do not stop these medications without the advice of your doctor.
Usually your doctor tells you whether to stop your medication for the exam.
What to expect when you arrive
Present yourself on the date of your appointment.
You will be asked to remove all upper body clothing and to wear a hospital jacket.
Your medication list
The technologist needs the list of your medications to complete the file. Make sure your list is up to date.
A small catheter
Then, you will lie down on a bed. A small catheter will be installed in a vein in your arm.
Electrodes on your skin
The electrodes will also be installed. These sensors, well attached to the skin, record the electricity emitted by your heart throughout the examination.
For a better electrical contact
The surface of our skin can attenuate the amplitude of the heart's electricity. To help better capture this electricity, it is necessary to lightly scratch the skin with a small sandpaper.
Blood pressure monitor
An apparatus for taking blood pressure is installed on your arm to record your blood pressure at different times during the examination.
Echocardiography at rest
The examination begins with a first echocardiography. It is commonly called; trans thoracic rest ultrasound.
Cardiac echography -1st part
A cardiac ultrasound allows the evaluation of the anatomy and the heart’s functions using ultrasound.
Same as for pregnant women
It is the same kind of test used to see the baby in pregnant women.
The difference is that, in this case, we will be looking at the heart and its ability to contract.
Trans thoracic echocardiography
The technologist or doctor places the ultrasound probe on the chest. Ultrasound will pass through the chest.
The technologist or doctor concentrates his recording on the heart’s work, particularly the left ventricle.
Several shots are required to see it from different angles.
Once these images are recorded, we go on to the second part, which is the injection of persantine.
We are now ready for the "simulation at effort" part
The intravenous persantin -2nd part
The injection of the persantin.
Persantine is a medication that is giving through the veins and takes 4 minutes to be fully administered.
This medication is a vasodilator, that is, it causes the arteries to dilate. It is administered to simulate your heart during an effort.
Throughout this phase of the test, your blood pressure and heart rate are monitored and recorded, and electrocardiograms (ECGs) are recorded.
The purpose of the exam is to speed up the heart
The purpose of the exam is to simulate an effort using persantine and verify its impact on the oxygenation of the heart muscle.
Persantine side effects are numerous but the most common are headaches, dizziness and nausea.
Some patients may experience chest pain as they struggle while others may experience shortness of breath.
Usually, these effects disappear with the injection of the antidote, aminophylline.
Additional doses of aminophylline may be administered if needed.
Second Ultrasound - Final Part
Once the injection of the persantine is complete, the ultrasound is repeated to compare with the resting images.
The technician or doctor may ask you to hold your breath to get better pictures.
And it's over
After the exam, you can get dressed and after a moment of observation in the waiting room with the person accompanying you, you can leave.
The results are sent to your doctor
The results will be communicated to the doctor who requested the examination.
You can request a copy for another doctor
You may ask that a copy of the result be sent to another doctor.
All you need to do is give the name and contact details of this doctor to the staff. You can ask for it at any time.
Comparison of images
Once the exam is completed, the cardiologist compares your resting images with those taken during persantine stimulation.
Why speed up the heart? What are we looking for?
The heart is a muscle. Increasing its work requires more oxygen. It feeds on arteries that are called coronaries. Coronary heart disease is responsible for blockages in the coronaries. These blockages can limit oxygen to the heart muscle.
Persantine acting on the arteries of the heart simulate effort.
Simulating physical activity with persantine will reduce the heart’s vitality in an area where the arteries are blocked.
The contraction will be less vigorous on certain regions of the heart compared to the images at rest.