An electrocardiogram, also called an ECG or EKG, records the electrical signals in your heart. It's a common test that's used to check the status of the heart and check for certain heart conditions.
An ECG is a noninvasive, painless test with quick results. During the test, sensors (also called electrodes or leads) that can detect the electrical activity of your heart are attached to your chest and sometimes to your limbs. The ECG monitor/EKG monitor displays its readings, which your doctor or technician will interpret later.
ECG's are quick, painless, and noninvasive. Your doctor may use an electrocardiogram to detect irregularities in your heart rhythm (arrhythmias), blocked or narrowed arteries in your heart (coronary artery disease), problems with your heart's chambers, how well certain ongoing heart disease treatments, such as a pacemaker, are working.
You may need a heart rhythm test if you experience any of the following possible signs and symptoms: heart palpitations, rapid pulse, chest pain, shortness of breath, dizziness, lightheadedness or confusion, or weakness, fatigue or a decline in ability to exercise.
No special preparations are necessary for a standard electrocardiogram. Tell your doctor about any medications and supplements you're taking because some can affect the results of your test.
During the test
An electrocardiogram can be done in a doctor's office or hospital and is often performed by a technician. You may be asked to wear particular clothes. Then you'll lie on an examining table or bed.
Electrodes, typically 10, will be attached to the chest and sometimes to your limbs. The electrodes are sticky patches applied to help record the electrical activity of your heart. Each one has a wire attached to an ECG monitor. If you have hair on the parts of your body where the electrodes will be placed, the technician may shave the hair to be sure that the patches stick.
You can breathe normally during the electrocardiogram. Make sure you're warm and ready to lie still. Moving, talking or shivering may distort the test results. A standard ECG only takes a few minutes.
As you lie on the examination table or bed, the electrodes will record the impulses that make your heart beat. The impulses are recorded by a computer and displayed as waves on a monitor or printed on paper.
After the test, you can resume your normal activities.
If you have a normal electrocardiogram, you may not need any other tests. If the results show an abnormal ECG or if your doctor prefers, he or she may recommend another ECG or a different diagnostic test, such as a stress test, coronary angiography, or holter monitor. Treatment depends on what's causing your signs and symptoms.