What is a stress test? The treadmill exercise or stress test is designed to see how well your heart works when you are exercising. It is used to test whether you have any evidence of coronary artery narrowing , the coronary arteries being the lifeline of blood to the heart. It is narrowing and blockage in coronary arteries that causes heart attacks and potentially death.
The test also gives information regarding your level of physical fitness and can be used to try and bring out any heart rhythm disturbances. The physician orders it when he/she wants to know what's your heart's response to exercise will be. Does your heart get better with exercise? Does your heart get worse with exercise? Do you get short of breath? Do you get chest pain?
How is it done? The technician starts by hooking you up to an electrocardiogram recording machine by attaching electrodes and wires to your body. Tape may be used to help hold the electrodes on your chest so that sweating during the exercise does not cause them to fall off. If you are allergic to adhesive tape, please let the technician know in advance. Next, a blood pressure cuff is attached to one arm. After a short rest period, you step onto the treadmill and the walk begins. The speed and/or steepness of the treadmill are gradually increased. During the test, the electrocardiogram, heart rate and blood pressure are periodically checked. The test continues until you have reached the target set by the physician, you reach the limit of your ability to exercies, develop concerning symptoms or if the physician is concerned about any findings. At the end of the test, you come off the treadmill and quickly lie down in bed while you electrocardiogram, heart rate and blood pressure continue to be checked. Finally, when you have returned to normal, the equipment is removed and you are discharged from the room.
The above example is typical of what an ECG looks like when you are walking/running on a treadmill. Keep in mind that a treadmill test should not be feared. We will only exercise you as far as YOU can go; NOT what we think you should be able to do. This is why we call this test "Symptom Limited". When you get your symptoms, we will stop.
Although nothing is absolutely guaranteed to be safe , it is very unlikely that a significant complication will occur during a treadmill test.
Acknowledgements: Contributors to this information were: Dr. R. Yee M.D., Arrhythmia Service, LHSC (UC), Dr. A. Krahn MD, Arrhythmia Service, LHSC (UC), and various staff members.