Exercise Stress Testing
Electrocardiography (ECG) is a test performed to record the electrical activity of the heart.
Exercise electrocardiography or Exercise Stress Testing is an ECG performed and monitored during exercise. This will allow us to see how your heart responds to the demands of physical activity.
During exercise the heart muscle requires blood in its arteries to pump. Areas where one or more of these arteries are blocked will struggle with oxygen supply which will in most cases be evident on the ECG.
An exercise stress test is a specific test performed to assess the hearts response to exercise and detect various forms of heart disease.
The aim of the test is to measure the heart's activity at rest and while walking. This enables the cardiologist to detect various abnormalities of the heart. It is generally a safe and painless procedure.
Exercise stress testing is performed to investigate:
- Chest pain
- Abnormal heart rhythms (eg.palpitations)
- Patients with cardiac risk factors such as high blood pressure, high cholesterol, diabetes and family history
- Your exercise capacity with known heart disease
- A safe level of exercise in patients with heart disease
- The effectiveness of stents or bypass surgery
- The future risk of heart related conditions
Exercise stress testing does not evaluate or predict the risk of future heart disease
An exercise stress test may not be performed on patients who:
- Are having a heart attack
- Have unstable angina
- Have very high blood pressure
- Have severe valvular abnormalities such as aortic stenosis
- Have severe lung disease
- Have mobility problems which will stop them from exercising
- Have any other non-cardiac disorders that can be aggravated by exercise
Before the test
- Do not eat for 4 hours prior to the test (you may drink water)
- Continue taking your medications unless your doctor has specified otherwise
- Wear or bring comfortable clothes and shoes to walk in
It is a requirement by law that we receive your consent to do your test. It is important that you understand what the test is about, how it is done and what the risks are. You will be given a form which will outline these things. If you have any questions please feel free to ask the technician who will be in the room with you when you sign the form.
How is the test done?
The test will be supervised by two Cardiac Scientists who will monitor your heart rate/rhythm and blood pressure during progressive levels of exercise.
Small sticky pads called electrodes are then attached to the chest to record the ECG. The electrodes need to have good contact with the skin to record the electrical impulses from the heart. Men with hairy chests will be shaved in spots where the electrodes will be placed. Ladies are able to leave their bra on and will be offered a gown. To ensure the electrodes have a good skin contact to pick up the electrical impulses from your heart the technician will also give your skin a little scrub with rough paper and then a wipe with alcohol. This removes the dead skin cells which form a barrier. You will find that this may sting a little and it will leave red patches on your skin. This is normal and will take a couple of days to go away. Some patients with extra sensitive skin may develop small blisters from the gel used on the electrodes. This is rare and will heal quickly.
With the electrodes and leads attached to your chest you will then be required to walk on the treadmill. This can be tricky at first but the speed is very slow for the first 3 minutes to give you time to get used to it. Every 3 minutes the treadmill will get slightly faster and steeper. If you are fit you may get to the stage where you will have to run.
During exercise it is important that you tell the staff if you feel any symptoms. The test will end when you have gone as long as you can, ideally when your heart rate has increased and you are feeling puffed.
After the exercise you will be monitored while your heart rate returns to rest. You can then dress and see the cardiologist for the results. The test will take approximately 1 hour.
Overall, the test is a good measure of the patient's heart condition. It however has certain limitations and is not 100% accurate. The results can be affected by:
- Abnormal resting ECG
- Anxiety/panic/inability to complete the test
- Failure to reach a target heart rate
What are the risks?
Possible adverse events related to stress testing include but is not limited to:
- Delayed onset muscle soreness
- Tiredness, fatigue
- Leg cramps
- Shortness of breath
- Chest pain
- Heart attack (approx. 2 in 10,000 tests)
- Death (approx. 1 in 10,000 tests)
How do I get my results?
A cardiologist will discuss the result with you upon completion of the stress test. This is not a consultation. If a consultation is required, you will require a new referral from your GP and a separate appointment will then be made for this.A report will also be sent to your referring doctor (usually within 24 hours). Your doctor can then discuss your results at your next appointment.