The Exercise EKG

Also referred to as a stress or exercise tolerance EKG, the exercise EKG is the same test performed for the resting EKG except the patient is performing exercise while the heart's electrical activity is recorded. Usually, the patient will use a treadmill or stationary bicycle during the test, progressing from easy to more difficult exercises that increase the demand on the heart. In some cases, the heart is stimulated using medications while the patient is lying still. The stress EKG allows the doctor to evaluate the performance of the heart and adequacy of coronary circulation under different levels of stress. Findings may be useful in the following evaluations:

To evaluate exercise tolerance and capacity
To distinguish chest pain that is cardiac in origin from pain caused by other problems
To evaluate heart rhythm at increased heart rates
To evaluate the effectiveness of medications used to manage chest pain associated with heart disease

In addition to the equipment used to perform the exercise EKG, a blood pressure cuff is placed on the patient's arm for continuous monitoring during the exercise. A baseline EKG and blood pressure reading are taken before exercise begins, then again during and after exercise. The exercise continues until one of the following endpoints:

The patient is exhausted (considered a "maximal" test).
The patient experiences chest pain.
The doctor detects EKG abnormalities.
There is a significant change, especially a drop, in blood pressure.
The patient's target heart rate is achieved.