Find over 200 print-friendly fact sheets about heart disease and related health topics.
An electrocardiogram (EKG or ECG) is a test
that checks for problems with the electrical activity of your heart. An EKG
heart's electrical activity into line tracings on
paper. The spikes and dips in the line tracings are called waves. See a picture
of the EKG components and intervals.
The heart is a muscular pump made
up of four chambers. The two upper chambers are called
atria, and the two lower chambers are called ventricles. A natural electrical
system causes the heart muscle to contract and pump blood through the heart to
the lungs and the rest of the body. See a picture of the
heart and its electrical system.
electrocardiogram (EKG or ECG) is done to:
Many medicines may change the results
of this test. Be sure to tell your doctor about all the nonprescription and
prescription medicines you take. If you take heart medicines, your doctor will
tell you how to take your medicines before you have this test.
Remove all jewelry from your neck, arms, and wrists. Men are usually
bare-chested during the test. Women may often wear a bra, T-shirt, or gown. You will be given a cloth
or paper covering to use during the test.
Talk to your doctor
about any concerns you have regarding the need for the test, its risks, how it
will be done, or what the results will mean. To help you understand the
importance of this test, fill out the
medical test information form(What is a PDF document?).
An electrocardiogram (EKG or ECG) is
usually done by a health professional, and the resulting EKG is interpreted by
a doctor, such as an
family medicine doctor,
You may receive an EKG as part
of a physical examination at your health professional's office or during a
series of tests at a hospital or clinic. EKG equipment is often portable, so
the test can be done almost anywhere. If you are in the hospital, your heart
may be continuously monitored by an EKG system; this process is called
During an EKG:
usually takes 5 to 10 minutes to complete.
The electrodes may feel cool when they
are put on your chest. If you have a lot of hair on your chest, a small area
may need to be shaved to put the electrodes on. When the electrodes are taken
off, they may pull your skin a little.
There is no chance of problems while having an
electrocardiogram (EKG or ECG). An EKG is a completely safe test. In most
cases, there is no reason why you should not be able to get an EKG.
The electrodes are used to transfer an image of the electrical activity
of your heart to tracing on paper. No electricity passes through your body from
the machine, and there is no danger of getting an electrical shock.
An electrocardiogram (EKG or ECG) is a
test that checks for problems with the electrical activity of your heart. An
EKG translates the heart's electrical activity into line tracings on paper. The
spikes and dips in the line tracings are called waves.
Your doctor will look
at the pattern of spikes and dips on your electrocardiogram to check the
electrical activity in different parts of your heart. The spikes and dips are
grouped into different sections that show how your heart is working. See a
picture that explains the
EKG components and intervals.
The heart beats in a regular rhythm, usually
between 60 and 100 beats per minute.
The tracing looks normal.
The heart beats too slow (such as less than 60 beats
The heart beats too fast (such as more than 100 beats per
The heart rhythm is not regular.
The tracing does not look
Reasons you may not be able to
have the test or why the results may not be helpful include:
Visit the American Heart Association (AHA) website for information on
physical activity, diet, and various heart-related conditions. You can search for information on heart disease and stroke, share information with friends and family, and use tools to help you make heart-healthy goals and plans. Contact the AHA to find your
nearest local or state AHA group. The AHA provides brochures and information
about support groups and community programs, including Mended Hearts, a
nationwide organization whose members visit people with heart problems and
provide information and support.
The Heart Rhythm Society provides information for
patients and the public about heart rhythm problems. The website includes a
section that focuses on patient information. This information includes causes,
prevention, tests, treatment, and patient stories about heart rhythm problems.
You can use the Find a Specialist section of the website to search for a heart
rhythm specialist practicing in your area.
The U.S. National Heart, Lung, and Blood Institute
(NHLBI) information center offers information and publications about preventing
CitationsU.S. Preventive Services Task Force (2012). Screening for coronary heart disease with electrocardiography: Recommendation statement. Available online: http://www.uspreventiveservicestaskforce.org/uspstf/uspsacad.htm.Other Works ConsultedChernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.Chou R, et al. (2011). Screening asymptomatic adults with resting or exercise electrocardiography: A review of the evidence for the U.S. Preventive Services Task Force. Annals of Internal Medicine, 155(6): 375–385.Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.U.S. Preventive Services Task Force (2012). Screening for coronary heart disease with electrocardiography: Recommendation statement. Available online: http://www.uspreventiveservicestaskforce.org/uspstf/uspsacad.htm.
March 6, 2012
Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology & George Philippides, MD - Cardiology
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