The most common type of stress test is an exercise stress test, which involves walking or running on a treadmill or pedaling an exercise bike while your heart rate is monitored.
But if you are not able to exercise enough to raise your heart rate for an exercise stress test, your doctor may recommend that you have a nuclear stress test with a pharmacologic agent (also called a chemical stress test). You may be a candidate for this type of stress test if you have experienced any of the following:
- Kidney transplant
- Heart transplant
- Recent knee or hip replacement
- Chronic obstructive pulmonary disease (COPD)
- Lung cancer
- Blood clots in the legs
- Arthritis that limits your ability to walk or ride a bike
- Obesity that limits your mobility
- Arrhythmia (abnormal heart rhythm)
- Have previously had a heart procedure
- Have a pacemaker
In a nuclear stress test with a pharmacologic agent, you sit in a chair or lie down while you're given a drug that makes the heart respond as if you were exercising. This is followed by a small dose of a radioactive isotope imaging tracer material.
Once the tracer is absorbed by your body, a camera takes detailed images of your heart—one when the heart is stressed, and another when it is at rest. The pictures are then compared to see how well blood flows into your heart.
If your doctor would like you to have a stress test, he or she will recommend the type of stress test that's best for you.