EXERCISE ELECTROCARDIOGRAM

What Is an Exercise ECG Test?
An exercise ECG test allows doctors to learn how well your heart functions when it is made to work harder. This test can help detect heart problems that may not be apparent at rest.
The exercise ECG test is done while you walk on a treadmill. During the test, an electrocardiogram (ECG or EKG) records the electrical activity of your heart.
[Other terms used to describe the exercise ECG test are: exercise test, stress test, and treadmill test.]

What Does It Show?
Doctors can see how well your heart functions during exertion by studying what happens during the exercise test.

• How long were you able to exercise? Generally, people with a healthy heart and in good physical condition are able to exercise longer.
• Did you have significant symptoms? It is normal to feel tired and short of breath during strenuous exercise. However, if you develop chest pain or become extremely short of breath, this may indicate a heart problem.
• What happened to your heart rate and blood pressure? The heart rate and blood pressure normally rise during exercise. An abnormal heart rate (too fast, too slow) or a fall in blood pressure may indicate heart disease.
• What did the ECG show? Certain changes in the ECG tracing may indicate that the heart muscle is not getting enough oxygen-rich blood. Sometimes, the ECG during exercise shows arrhythmias (abnormal heart rhythms).

The exercise test is especially useful in diagnosing blockages in the coronary arteries (the vessels that carry blood to the heart). When the coronary arteries are blocked or narrowed, the heart muscle may not be getting enough oxygen during exercise. This often results in symptoms of angina (chest pain) and abnormal changes on the ECG.

Preparing for the Test

• Do not eat or drink for 3 hours prior to the test. This will prevent the possibility of nausea, which may accompany vigorous exercise after eating. [If you are diabetic and take medications for diabetes, get special instructions from your doctor.]
• If you are currently taking any heart medications, check with your doctor. He or she may ask you to stop certain medications a day or two before the test. This can help get more accurate test results.
• Wear loose, comfortable clothing that is suitable for exercise. Men usually don't wear a shirt during the test, and women generally wear a bra and a lightweight blouse or a hospital gown. You should also wear comfortable walking shoes or sneakers.
• Before the test, you'll be given an explanation of the test and you'll be asked to sign a consent form. Feel free to ask any questions about the procedure.
• Several areas on your chest and shoulders will be cleansed with alcohol and an abrasive lotion, to prepare the skin for the electrodes. Men may need to have areas of their chest shaved, to ensure that the electrodes stay in place.

What Happens During the Test?
The exercise ECG test can be performed in the doctor's office or at the hospital.
A trained technician (or a nurse) will place several electrodes (small sticky patches) on your chest and shoulders to allow recording of the ECG during exercise. The electrodes are connected by wires to an ECG machine. A cuff will be applied to your arm to monitor your blood pressure.
You will be shown how to step onto the treadmill and how to use the support railings to maintain balance. The treadmill starts slowly, and then the speed and incline are increased gradually. [If you pedal a stationary bicycle, it feels easy to pedal at first, then it gradually gets harder.]
Your blood pressure will be checked every few minutes, and the ECG will be carefully watched for abnormal changes. You will be instructed to report any symptoms, such as chest pain, shortness of breath, leg fatigue, or dizziness.
The test may end when you become too tired to continue or when you experience significant symptoms. Other times, the test may be stopped when you reach your peak heart rate or when your ECG shows abnormal changes.
After the exercise portion of the test is over, you'll be helped to a chair or a bed. Your blood pressure and ECG will be monitored for another 5 to 10 minutes while you recover. The technician will remove the electrodes and cleanse the electrode sites.

How Long Does It Take?
You should allow 45 minutes to one hour, which includes preparation for the test, the exercise portion, and the recovery period.

Is the Exercise Test Safe?
The exercise test is generally safe. A small amount of risk does exist, however, because it stresses the heart. Possible rare complications include abnormal heart rhythms and a heart attack. Experienced personnel are available to handle any emergency.

The Results
The doctor conducting the test may be able to give you preliminary results before you leave. A complete interpretation may take several days.
If the test is abnormal or inconclusive, your doctor may order additional tests.
The information gained from the exercise test helps your doctor make an accurate diagnosis and develop a treatment plan that's best for you.