An exercise electrocardiogram (EKG or ECG) is a test that checks for changes in your heart while you exercise. Sometimes EKG abnormalities can be seen only during exercise or while symptoms are present. This test is sometimes called a "stress test" or a "treadmill test." During an exercise EKG, you may either walk on a motor-driven treadmill or pedal a stationary bicycle.
The heart is a muscular pump made up of four chambers . The two upper chambers are called atria, and the two lower chambers are called ventricles. A natural electrical system causes the heart muscle to contract and pump blood through the heart to the lungs and the rest of the body.
An exercise EKG translates the heart's electrical activity into line tracings on paper. The spikes and dips in the line tracings are called waves.
A resting EKG is always done before an exercise EKG test, and results of the resting EKG are compared to the results of the exercise EKG. A resting EKG may also show a heart problem that would make an exercise EKG unsafe.
Why It Is Done
An exercise electrocardiogram is done to:
- Help find the cause of unexplained chest pain or pressure.
- Help decide on the best treatment for a person with angina.
- See how well people who have had a heart attack or heart surgery are able to tolerate exercise.
- Help find the cause of symptoms that occur during exercise or activity, such as dizziness, fainting, or rapid, irregular heartbeats (palpitations).
- Check for a blockage or narrowing of an artery after a medical procedure, such as angioplasty or coronary artery bypass surgery, especially if the person has chest pain or other symptoms.
- See how well medicine or other treatment for angina or an irregular heartbeat is working.
- Help you make decisions about starting an exercise program if you have been inactive for a number of years and have an increased chance of having heart disease.
Exercise electrocardiograms are not recommended if you're healthy and have no symptoms of heart disease.1