How is a stress test performed?
Before a stress test: The doctor obtains a detailed history and performs a physical examination. The doctor would advise certain pre-procedure instructions. You may have to skip certain medicines on the day of the test.
During a stress test: Your entire stress test, including the prep time, would take about 45 minutes to an hour. The actual test takes only around 15-20 minutes. The patient would have to walk on a treadmill or pedal a stationary bicycle. As time passes, both the treadmill slope and speed increase at a fixed time interval.
Any patient who is unable to exercise would receive drugs through veins that would mimic the effects of exercise by increasing blood flow to the heart.
The nurse or technician will place electrodes on the chest, legs, and arms. Some areas of the body may need to be shaved to help the electrodes stick. The electrodes are connected to an electrocardiogram (ECG) machine, which records the electrical signals from the heart. A cuff is placed on the upper arm to monitor blood pressure during the test. Throughout the test, your blood pressure, ECG, and heart rate are recorded.
The patient continues exercising till the heart rate reaches the target set or till any of the following signs and symptoms occur (Your target heart rate is calculated by the system based on your age and weight.):
- Chest discomfort or pain
- Difficulty in breathing
- Abnormally high or low blood pressure
- Cardiac arrhythmia
- Abnormal changes in the ECG
The test is safe and performed under supervision. The patient may stop anytime they feel uncomfortable.
After a stress test: After the patient finishes exercise, they may be asked to stand still for several seconds and then lie down for some time while still being monitored. The doctor would observe for any abnormalities in heart rate and breathing while returning to normal. Once a stress test is complete, the patient can return to their normal activities unless they are advised otherwise. Studying the results of the stress test would help the doctor make a diagnosis and advise an appropriate treatment plan.