TREADMILL (STRESS TEST)
The treadmill is a test in cardiology that evaluates, indirectly, possible blockages in the coronary arteries.
It also helps evaluate the cardiovascular condition.
Recordings of important information
Complementary information on the heart rate and on the blood pressure after effort is also recorded during a treadmill test.
The treadmill test is simple, but asks for a physical effort. The goal is to see how the heart reacts to an effort.
No particular preparation
The treadmill test does not require any preparation. It is not necessary to fast, but we suggest eating something light before this exam.
An appointment is necessary for the treadmill test.
The day of your exam, you must bring comfortable shoes to your appointment. Sandals or high heel shoes are not permitted for security reasons.
You must then remove all upper body clothing and wear a hospital gown.
The technologist needs your updated list of medication to complete the information. You must therefore remember to carry your list with you.
You will be asked to lie on a bed for the installation of electrodes. These sensors placed on your skin record the electricity produced by your heart during the test.
For a more effective skin contact
The keratin on our skin can reduce the electrical amplitude of the heart. To prevent this, the skin is lightly scratched with a piece of sandpaper.
A box at your waist
The sensors are connected with wires to a box that records information. This box is at your waist during the test.
Tensiometer on your arm
A device to measure your blood pressure at different moments during the test is installed around your arm.
We are now ready for the exam
Doctor, I cannot run!
Yes, the treadmill exam demands an effort. However, it does not necessarily require jogging or running.
The technologist may demonstrate how to walk on the treadmill. Do not hesitate to ask him or her.
There are different ways to increase your heart rate on the treadmill. The speed and the inclination of the machine intensify throughout the test.
For patients who are less physically active, there are slower speeds and smaller inclinations that can be set on the treadmill. A person in better shape will be tested on a different protocol, since the heart rate would not increase quickly enough under the same conditions.
The goal is to increase the heart rate
The goal of the test is to have your heart rate increase to a certain level in order for the exam to be worth it.
The heart rate that must be attained varies with age.
Why accelerate the heart? What we are looking for?
The electricity produced by the heart can be recorded through the little sensors placed on the skin. This recording is called an electrocardiogram (ECG). The ECG is proper to each individual, just like a fingerprint.
Any interference with the natural electric flow of the heart will modify the recordings.
The lack of oxygen in a given region of the heart also changes the results seen on the ECG.
Coronary heart disease is responsible for blockages in the coronary artery. These blockages may limit the oxygen entering the heart muscle. Physical activity generates a more important circulation in the muscles. The heart must therefore increase its intensity to respond to the demand.
However, the heart is also a muscle. An increase in its intensity also means that it too needs more oxygen. If there happens to be one or more blockages that limit the amount of oxygen to the muscle, the heart suffers.
This suffering modifies the electricity produced by the heart. These impairments will appear on the electrocardiogram produced during the treadmill test.
Pieces of advice
You should walk on the treadmill as if you were walking on the street. You do not walk leaning forward on the street. It is the same on the treadmill. Take long strides. Short, fast steps will tire you out quickly.
Preferably, do not hold on to the bar at the front of the treadmill. You may however place one hand on it to gain confidence.
It is important to follow the technologist’s recommendations. To obtain the most accurate results, he or she will encourage you to give it all you have.
Your blood pressure is monitored
Throughout the exam, the technologist will monitor your blood pressure.
The stages of the exam
The treadmill works by stages. The inclination and the speed are constant for two to three minutes according to the procedure chosen.
We can see how your heart responds to the effort.
The length of each stage allows your heart to respond to each level. Once the heart has shown its reaction, we move on to the next level until we obtain the desired heart rate necessary for the exam to be valid according to your age.
I failed the treadmill test
Nobody fails or succeeds a treadmill test. However, we can make conclusions.
You have the final word!
You may ask to end the exam at any moment.
The technologist or the doctor will want to know the reasons for your demand. Sometimes, a little encouragement will give you the energy needed to attain the desired heart rate. You are not doing all this for nothing.
Other reasons to end prematurely
The doctor or technologist may end the test at any moment. Your difficulties to walk appropriately on the treadmill or abnormal blood pressure during the exam are two examples of reasons why the test may end quickly.
Normal dizziness at the end of the treadmill test
Do not be surprised to feel dizzy when the treadmill stops. This is caused by you walking, but not moving forward. It will come back to normal quickly.
Well-deserved resting period
You will be asked to sit and your resting period will be monitored for three minutes. During this period, you will catch your breath, and your blood pressure and heart rate will be monitored.
A towel is available if needed.
You may now change back into your regular clothes and leave.
The results are sent to your doctor
The results are communicated to the doctor who asked for the exam.
You may ask for a copy for another doctor
You may ask for a copy of your results to be sent to another doctor. You simply have to give the name and contact information to the personnel.
You may ask at any moment.
Certain exams may be inconclusive
It is possible that the treadmill test is inconclusive for a variety of reasons.
· Insufficient effort to accelerate the heart rate
· Electrical anomalies on the ECG
· Electrical, doubtful irregularities without possible conclusions
A complementary exam may be asked for by your doctor.
Your doctor may also ask for more complementary tests if your results seem abnormal.
The treadmill test is an easy test to complete and it allows for much information to be recorded.
It is the first exam prescribed by a doctor to verify if there are any blockages in the coronary arteries.
Subsequent, complementary exams are more complex, longer and more precise. It must be noted, however, that it is quite frequent that complementary tests do not show any irregularities even if the treadmill results were abnormal. We call these “false positives”.