An electrocardiogram is used to monitor your heart. Every beat of your heat is triggered by an electrical impulse that is normally generated by special cells in the upper right chamber of your heart. Also known as ECG or EKG, an electrocardiogram records these particular electrical signals as they travel through your heart.
Your doctor uses an electrocardiogram to search for any patterns among these heart beats and rhythms to diagnose a number of heart conditions. This procedure is a non-evasive, painless test with quick results. You may get to know the results on the same day as your electrocardiogram, or at your next appointment.
An electrocardiogram is a harmless procedure, but there are few potential risks.
You may experience some minor discomfort, similar to removing a bandage when the electrodes are taped to your chest in order to measure your heart's electrical signals and when they are removed.
It is rare for a reaction to the electrode tape to cause redness and swelling of your skin.
A stress test, in which an ECG is performed while you exercise or after you take medication that mimics the effects of exercise, may cause irregular heartbeats or, rarely, a heart attack.
These side effects are the result of the exercise or medication, not by the ECG itself.
There is no risk of electrocution during an electrocardiogram. The electrodes placed on your body only record the electrical activity of your heart. They do not emit electricity.
Here’s what you can expect before, during, and after your procedure.
An electrocardiogram can be done in the doctor's office or hospital, and is often performed by a technician.
After changing into a hospital gown, you'll lie on an examining table or bed.
Electrodes ,often 12 to 15 ,will be attached to your arms, legs and chest. The electrodes are sticky patches applied with a gel or tape to help detect and conduct the electrical currents of your heart. If you have hair on the parts of your body where the electrodes will be placed, the technician may need to shave the hair so that the electrodes stick properly.
You can breathe normally during the electrocardiogram. Make sure you're warm and ready to lie still, however. Moving, talking or shivering may distort the test results.
A standard ECG takes just a few minutes. As you lie on the examination table or bed, the electrodes will record the impulse that makes your heart beat. The impulses are recorded as waves on a computer monitor or printed on paper.
Your doctor will look at the waves to see if the impulses are traveling normally. If you have a heartbeat irregularity that tends to come and go, it may not be captured during the few minutes a standard ECG is recording.
To work around this problem, your doctor may recommend another type of ECG: Holter monitoring. Also known as an ambulatory ECG monitor, a Holter monitor records your heart rhythms for an entire 24-hour period.
Wires from electrodes on your chest go to a battery-operated recording device carried in your pocket or worn on a belt or shoulder strap. While you're wearing the monitor, you'll keep a diary of your activities and symptoms. Your doctor will compare the diary with the electrical recordings to try to figure out the cause of your symptoms.
If your symptoms don't occur often, your doctor may suggest wearing an event recorder. This device is similar to a Holter monitor, but it allows you to record your heart rhythm just when the symptoms are happening. You can send the ECG readings to your doctor through your phone line.
If your heart problems occur most often during exercise, your doctor may ask you to walk on a treadmill or ride a stationary bike during an ECG. This is called a stress test.
If you have a medical condition that makes it difficult for you to walk, medication may be injected to mimic the effect of exercise on your heart.
After the Procedure
Usually, your doctor will be able to tell you the results of your ECG the same day it's performed. If your electrocardiogram is normal, you may not need any other tests.
If the results show there's a problem with your heart, you may need a repeat ECG or other diagnostic tests, such as an echocardiogram. Treatment depends on what's causing your signs and symptoms. You can resume your normal daily activities after your electrocardiogram.