An exercise stress test is one of the tools that your doctor can use to evaluate how well your heart responds to the demands placed on it.  It gives him or her an indication as to how healthy your heart is.  Other names that an exercise stress test is known by include: graded exercise test (GXT), stress test, treadmill test, and exercise/stress electrocardiogram. 

     Your doctor may recommend a stress test if you have been experiencing symptoms suggestive of coronary artery disease, such as chest/arm/jaw pain or unusual shortness of breath.  He/she may also want you to perform the test if you have multiple risk factors for heart disease, such as being overweight, a smoker, a diabetic, or having high cholesterol and/or high blood pressure.  If you have been experiencing an irregular heartbeat, your doctor may use the test to see if there is a heart-related cause.  The stress test can also be used to check the effectiveness of a procedure performed to increase blood flow to your heart, such as with bypass surgery.  Or, it may be used to determine your ability to safely resume activities of daily living after a heart attack.  Another use for the test can be to determine your state of fitness so that a safe level of exercise can be prescribed to you if you are interested in starting a program.

     A stress test typically requires you to either walk on a treadmill or ride a stationary bike while the workload becomes progressively harder at specific intervals.  During the test, your heart rate, blood pressure, and the electrical activity of your heart (by means of an electrocardiogram) are monitored.  Furthermore, throughout the test you are asked to rate how difficult you perceive the exercise to be and if you are experiencing any symptoms or discomfort.  

     To increase the sensitivity and specificity of the test, your doctor may choose to have images taken of your heart, such as through echocardiography or nuclear imaging, to be used in combination with the electrocardiogram (ECG or EKG).  Another alternative mode of testing involves non-exercise, pharmacologic-induced stress.  Your doctor would recommend this form of testing if you are unable to exercise due to such conditions as orthopedic limitations, a de-conditioned health state, or the presence of a disease that would not allow you to reach the level of stress needed to produce valid results.

     Depending on the results of the stress test, your doctor may send you for further testing, such as a cardiac catheterization.  Or, he may suggest lifestyle changes that would promote your health and decrease your risk for disease.  If you have any questions before the stress test or after, don't hesitate to ask your doctor.