Stress Test (Treadmill or Bicycle)
A stress test or exercise tolerance ECG test monitors your heart's rhythm and electrical activity and your blood pressure during exercise
What is a Stress Test and how does it work?
A stress test or exercise tolerance ECG test monitors your heart's rhythm and electrical activity and your blood pressure during exercise, takes place on a treadmill or a bicycle within the clinic.
When do I need a Stress Test?
When your doctor suspects coronary artery disease:
Chest pain or shortness of breath with exertion
Decreased exercises tolerance of unknown reason
Health screening investigations
Yearly check after heart attack or after revascularisation procedures (coronary stent implantation or Bypass surgery)
An exercise tolerance test is often used as part of a screening medical for certain jobs with safety critical responsibilities such as public service drivers, i.e. taxi, bus and train drivers, particularly after a heart attack or chest pain. Pilots and some categories of motor racing licenses may also require this test
During the test
During the test, ten electrodes are attached to your chest for continuously monitoring your 12 lead ECG and an inflatable cuff is placed around your upper arm to monitor your blood pressure.
The test commences by taking resting measurements for the blood pressure and ECG. Then, you will stand on the treadmill which when you are ready, will start moving and every 3 minutes the speed and slope will be increased. The standard protocol is the Bruce protocol, with the modified Bruce protocol used if a reduced level of effort is required.
The time on the moving treadmill will continue until certain criteria are achieved. Such criteria may be attaining an age related predicted maximum heart rate, you experience chest pain or chest pain equivalent symptoms or significant pathological ECG changes or if your blood pressure or heart rate exceed or do not follow expected patterns, or you become tired and cannot continue. You are ultimately in charge, and if you wish to stop the test, it will be stopped.
It may be necessary to stop some medications, especially Betablockers, prior to an exercise test; if this is the case, your consultant will advise this.
The test usually lasts 30 minutes and afterwards you are able to continue a normal day; however if you are not used to exercise, you may feel fatigued.
Results are usually available instantly and your consultant may wish to discuss them immediately with you, rather than requiring you to attend a separate appointment.
A medication-induced stress test combining Echocardiography and ECG evaluation at the same time.
What is Pharmacological Stress-Echocardiography and how does it work?
Dobutamine is an intravenous medication causing your heart rate to rise gradually in relation to the administered dose. The doses applied is being calculated depending on the body weight of the patient.
Before, during and after administration of different Dobutamine dosages, the ECG is being monitored for specific changes and the trans thoracic echocardiography image is being evaluated for regional wall motion abnormalities.
Both would be signs of coronary artery disease and myocardial schema.
This test is more sensitive and more specific than a simple treadmill or bicycle stress test, especially in female patients.
Why would you need Pharmacological Stress-Echocardiography?
When your doctor suspects coronary artery disease and you cannot perform an exercise stress test for various reasons: for example immobility, muscular fatigue, age.
During the Pharmacological Stress-Echocardiography test
You will be lying on your left side as for the simple trans thoracic echocardiography. The ECG electrodes and a BP cuff are being placed for continuous monitoring. An adrenalin like medication, Dobutamine, is being administered through a vein so a small venous catheter will be placed in your arm or hand.
During the test your heart rate will increase, and you may feel your heart beating fast and strong. Irregular beats may arise. Some patients feel light nausea or “funny feeling” like goose bumps on their scalp, this is due to the medication.
In case you feel chest pressure, shortness of breath, pain in your neck or back of your chest between the shoulder blades or even mid-belly pain, the test will be considered positive and will be stopped. All of these are angina symptoms and make the presence of coronary artery disease highly positive.
The medication has a short half-life, it will wear off shortly after the procedure is done. No special aftercare is needed.