During the ECG
An electrocardiogram can be done in a doctor's office or hospital and is often performed by a technician. You may be asked to change into a hospital gown. Then you'll lie on an examining table or bed.
Electrodes — typically 10 — will be attached to 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 a monitor. If you have hair on the parts of your body where the electrodes will be placed, the technician may shave the hair so 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 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 ECG
You can resume your normal activities after your electrocardiogram.
Your doctor will look at the waves recorded during your test to see if the impulses are traveling normally. He or she will be able to tell you the results of your ECG the same day it's performed or at your next appointment.
If your electrocardiogram is normal, you may not need any other tests. If the results show an abnormality with your heart, you may need another ECG or other diagnostic tests, such as an echocardiogram. Treatment depends on what's causing your signs and symptoms.
Feb. 02, 2017
- Electrocardiogram. National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/health/health-topics/topics/ekg. Accessed Aug. 12, 2016.
- Stress testing. National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/health/health-topics/topics/stress/. Accessed Aug. 12, 2016.
- Goldman L, et al., eds. Electrocardiography. In: Goldman-Cecil Medicine. 25th ed. Philadelphia, Pa.: Saunders Elsevier; 2016. https://www.clinicalkey.com. Accessed Aug. 12, 2016.
- AskMayoExpert. Ambulatory heart rhythm monitoring. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2016.
- Barbara Woodward Lips Patient Education Center. Supraventricular tachycardia (SVT). Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2012.
- Chou R. Cardiac screening with electrocardiography, stress echocardiography, or myocardial perfusion imaging: Advice for high-value care from the American College of Physicians. Annals of Internal Medicine. 2015;162:438.
- Asirvatham SJ, et al. Electrocardiogram mapping-reentry: Final frontier? Circulation: Arrhythmia and Electrophysiology. 2014;7:760.
- Pfenninger JL, et al. Office electrocardiograms. In: Pfenninger and Fowler's Procedures for Primary Care. 3rd ed. Philadelphia, Pa.: Elsevier; 2011. https://www.clinicalkey.com. Accessed Aug. 12, 2016.
- Chen YH, et al. Soft, comfortable polymer dry electrodes for high quality ECG and EEG recording. Sensors. 2014;14:23758. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4299086/. Accessed Aug. 12, 2016.
- Nestler DM, et al. Impact of prehospital electrocardiogram protocol and immediate catheterization team activation for patients with ST-elevation-myocardial infarction. Circulation Cardiovascular Quality outcomes. 2011;4:640.
- Gibbons RJ, et al. Use of echocardiography in Olmsted County Outpatients with chest pain and normal resting electrocardiograms seen at Mayo Clinic Rochester. Mayo Clinic Proceedings. 2015;90:1492.
- What causes an arrhythmia? National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/health/health-topics/topics/arr/causes. Accessed Oct. 7, 2016.
- Riggin EA. Allscripts EPSi. Mayo Clinic, Rochester, Minn. July 28, 2016.
- Riggin EA. Allscripts EPSi. Mayo Clinic, Rochester, Minn. Sept. 29, 2016.
- Murphy JG, et al., eds. Indications for invasive and noninvasive electrophysiologic testing. In: Mayo Clinic Cardiology: Concise Textbook. 4th ed. New York, N.Y.: Oxford University Press; 2013.
- Gerstenfeld EP, et al. Atrial fibrillation ablation: Indications, emerging techniques and follow-up. Progress in Cardiovascular Diseases. 2015;58:202.
Electrocardiogram (ECG or EKG)