03 February 2018
STRESS ECHO WITH TREADMILL
The treadmill is a test used in cardiology to assess, in an indirect way, the presence of blockages in the coronary arteries.
It also can assess your exercise tolerance (or exercise capacity)
Certain tests can be inconclusive.
A complementary test may be required by your doctor thereafter.
One of these complementary tests is a treadmill done in conjunction with an echocardiogram. Thereby, this is called a Stress echo.
Two for One
Like the name says, it is the combination of a treadmill and a cardiac echography.
The goal is to clarify the results of an ambiguous treadmill test, to confirm the result or more precisely determine the location of the blockages.
Relatively easy test
It is a relatively easy test but which takes more time to do. We want to “see” how the heart works during exercise.
We must look at the heart at rest and again immediately after the treadmill exercise.
No particular preparation
There is no need for a specific preparation nor to be fasting.
However, it is recommended not to eat too much before this test.
Your doctor will indicate to you if it is necessary to temporarily stop taking some of your medication for the test. Otherwise, you take your regular medication as usual.
It requires an appointment
You usually do this test as an outpatient, but it needs to be scheduled.
How to prepare for the test
The day of your test, you arrive to your appointment with comfortable shoes. Sandals or high-heels are not allowed for safety reasons.
You will be asked to take off your upper body clothes and to wear a hospital gown.
The technologist will collect information on your current medication. It is important to have an up-to-date list.
You will have to lay flat on your back for the installation of the electrodes. These sensors, connected to the skin, record the electricity generated by your heart throughout the test.
For a better electrical contact
The keratin on our skin can attenuate the amplitude of the electrical activity of the heart. In order to get a better contact, the skin is scratched with a mildly abrasive paper.
Echocardiogram at rest
The test begins with the first echocardiogram. It is the resting echocardiogram.
Cardiac echography (echocardiography) is a test used to assess the anatomy and the function of the heart using ultrasounds.
As for pregnant women
It is a test of the same nature as the one used to see babies in pregnant women.
In our case, it is the heart that we want to see and particularly its contraction pattern.
Transthoracic Echocardiogram – 1st part
The echography probe will be placed on the chest. The ultrasounds will pass through the thorax.
The technologist will focus on recording the work of the left ventricle. Various viewing angles may be used to see the heart properly.
Once this is recorded, the second part of the test will start: the treadmill test.
Treadmill – 2nd part
A recording box at your waist
A recording box will be attached to your waist and connected to all the electrodes on your chest.
A pressure cuff on your arm
A pressure cuff will be placed around your arm to record your blood pressure blood at various times during the test.
We are now ready for the next phase: exercise
In the vast majority of cases, patients scheduled for a stress echo are already familiar with a treadmill stress test.
The goal of the test is to accelerate the heart rate
The goal of the test is to accelerate your heart rate to a certain level so the cardiologist can draw conclusions
The target heart rate varies with age.
You have to walk on the treadmill as if you were walking on the street. You do not walk leaning forward on the street; it’s the same on the treadmill.
Make good steps. The short, fast steps will exhaust you for nothing.
It is preferable not to hold the bar which is in front of the treadmill.
Follow the recommendations of the technologist. You may be asked to go a bit faster, to push a bit more. This is to achieve the best test result.
Your blood pressure is monitored
Throughout the test, the technologist takes your blood pressure with the blood pressure cuff.
The test progresses by stages
The treadmill works by stages, i.e. the slope and speed are programmed for periods of 2 to 3 minutes depending on the program used.
We want to see how your heart responds to exercise
The duration of each period allows your heart to respond to a certain level of stress. Once achieved, we move on to the next level until we obtain the heart rate necessary to the validity of the test.
Dizziness when the treadmill stops
When the treadmill is stopped, you may feel dizzy. This is due to the fact that you were walking without actually moving. This sensation disappears quickly.
Why accelerate the heart rate - what are we looking for?
Coronary heart disease is caused by accumulation of fatty plaques inside the coronary arteries. These plaques /blockages can limit oxygen supply to the heart muscle.
Physical activity is associated with increased oxygen demands to active muscles. To match the increased demand, blood circulation must increase and the heart must work harder to pump more blood to the body muscles.
The heart is also a muscle. Its increased work also requires more oxygen. In the presence of one or more blockages in the coronary arteries, oxygen is not delivered in sufficient quantity and the heart may signal that it is suffering.
This suffering modifies the strength of the muscular contraction of the heart in affected areas. This is why a second echocardiogram is performed immediately at the end of the treadmill.
The images of your heart working at rest are compared with the images of your heart during physical effort. Each segment of the left ventricle is assessed. (There are 16 segments)
We are looking for areas of the heart which contract less effectively during physical stress than at rest. It is a way of showing that decreased contraction strength in a muscle area during stress could be secondary to a significant blockage in the coronary artery supplying that area.
The last phase: the second echocardiogram
When the treadmill is stopped, you will be promptly directed to the exam table to record the contraction of the cardiac muscle.
We must record it quickly before the heart rate slows down. (We have one minute or less to take all the recordings).
We may ask you to hold your breath to get better images. It is not always easy but with your cooperation we can get good images.
And it’s done
After this second recording, you can get dressed and leave.
The results are sent to your doctor
The results will be communicated to the doctor who ordered the test.
You can ask for a copy for another doctor
You can ask that a copy of the result be sent to another doctor. You just have to give the name and address of this doctor to the staff.