What is an electrocardiogram (EKG)?

An electrocardiogram (ECG) is a diagnostic test that is used to detect abnormalities in the heart's rhythm. It also can provide important information about damage to the heart, valve disorders, structural abnormalities in the heart's walls, and more.

An electrocardiogram (ECG or EKG) is a simple, painless test to measure the heart’s electrical activity. The heart generates electrical signal that flows through your body. During this test, small electrical sensors, called electrodes, are put on your skin to sense the electricity that began in your heart. This activity is then turned into a graph, which can give doctors an idea of whether your heart is beating normally. This is a common diagnostic test for atrial fibrillation.

An EKG is a measurement tool used to view the electrical activity of the heart. It can show changes in normal activity and is also used as a diagnostic tool for cardiologists who are trying to determine if your heart has electrical conductivity issues.

An EKG (short for electrocardiogram) is a fast and painless test that checks for problems with the electrical activity of your heart. An EKG translates the heart's electrical activity into line tracings on a paper. The spikes and dips in the line tracings are called waves. From examining these waves a cardiologist or other qualified medical staff can determine if certain areas (but not all) of the heart muscle have been damaged.

Holter and 30 Day event monitors are small and portable EKG recording units applied by a trained EKG technician. Patients are able to go about their daily routine while the unit records their heart rhythm for later evaluation.

Dr. Abdul J. Tajik, MD
Cardiologist (Heart Specialist)

An electrocardiogram (ECG) measures the electrical activity of your heart. It provides information about the heart rhythm and indirectly measures the size of the heart.

Dr. Steven C. Port, MD
Cardiologist (Heart Specialist)

An electrocardiogram, also known by the abbreviations ECG and EKG, detects low-voltage electrical activity of the heart through electrodes placed on the chest. Physicians, and sometimes computer programs, interpret the pattern of the electrocardiogram for deviations from normal. It is commonly used to document heart rhythm and diagnose a prior heart attack, a heart attack in progress and thickening of the heart as may be seen with long-standing high blood pressure.

An electrocardiogram, often referred to as an ECG or an EKG (’cause the Germans spell cardiogram with a K) is a non-invasive, painless test that measures your heart’s electrical impulses. Typically, electrodes are pasted onto your chest, arms, and legs (back in the day, they used little suction cups). The electrodes carry the signal from your heart to a monitor so you can see:

  • how fast your heart is beating
  • whether your heart rhythm is steady or irregular
  • the strength and timing of electrical signals in each part of your heart
An electrocardiogram (EKG) is a noninvasive test graphically showing how the electrical impulses flow through the heart. Abnormalities may indicate that a heart attack has occurred in the past.
Dr. Douglas E. Severance, MD
Family Practitioner

An EKG (electrocardiogram or ECG) is a simple test your doctor can do to assess your heart muscle or valve function while diagnosing atrial fibrillation. When the EKG is done at the time of an arrhythmia, the doctor can see the arrhythmia happening. To diagnose paroxysmal or occasional atrial fibrillation, you may have to wear a portable ECG, called a Holter monitor, or event monitor. This type of arrhythmia comes and goes, and it may not be detected at your doctor's visit. The EKG will show your doctor how fast your heart beats and also the rhythm (whether steady or chaotic). This test also makes a record of the strength and timing of electrical signals in the heart. Depending on the results of the EKG and the cause of your atrial fibrillation, your doctor may recommend lifestyle changes, such as stopping alcohol, coffee, cigarettes and a medication. Or if the atrial fibrillation is persistent, your doctor may prescribe medications and/or electrical cardioversion.

An electrocardiogram (ECG, EKG) is often the first test your doctor will order to try and confirm a diagnosis of atrial fibrillation. The ECG is a simple and painless test that gives an accurate recording of the heart's electrical activity. This exam can detect the irregular rhythm and rapid heart rate of atrial fibrillation, check to see if you had a previous heart attack, and determine if you have other kinds of abnormal heart rhythms. The ECG cannot detect atrial fibrillation if you have so-called paroxysmal atrial fibrillation, which comes and goes; then your doctor will likely use other, portable tests to get a recording of your heart's electrical system while you are at home and at work.

An electrocardiogram (ECG or EKG) is one of the simplest and fastest procedures used to evaluate the heart. Although cardiologists apply different criteria when evaluating women’s and men’s electrocardiograms, ECG is considered to be as reliable in assessing heart-disease risk in women as it is in men. It is painless, risk-free and usually takes less than 30 minutes.

Electrodes (small, plastic patches) are placed at certain locations on the chest, arms and legs. The electrodes are connected by lead wires to an ECG machine, which produces a tracing of the electrical activity of the heart. The tracing can be measured, interpreted by the machine’s computer and printed out for the physician’s information and further interpretation.

What to expect:

  • An ECG is often performed in an office visit.
  • Electrodes are placed on your skin.
  • Electrodes transmit, but do not generate, impulses.
  • The test will last about 30 minutes.
  • You should be able to go home on your own.
Dr. Kathleen Handal, MD
Emergency Medicine Specialist

If you’re in the ER because of chest pain, or you have a cardiac history, you will have an electrocardiogram (ECG, also called EKG) done and may remain hooked up to a cardiac monitor. An ECG does not hurt but requires you to lie still and silent during the test. You will be attached to a recording machine by several sticky pasties placed across the chest and on your limbs or sides. ECG machines record the electrical activity of your heart as lines (wave forms) on a small strip of graph paper. The computer records several beats simultaneously, as viewed from 12 or 16 sides of the heart. Most ECG machines are capable of interpreting the tracing as it prints the paper copy. The "machine" interpretation is not to take the place of a doctor’s interpretation.

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Doc's ER Survival Guide (DocHandal's Guides)

Few people get through life without at least one trip to the emergency room (ER), either as a patient or support person for a family member or friend. Doc’s ER Survival Guide is designed to help...

An electrocardiogram (ECG or EKG) is a graphic record of the electrical activity of the heart as it contracts and rests. To record the ECG, a technician positions a number of small contacts on your arms, legs and chest to connect them to an ECG machine. An ECG can detect arrhythmias and heart damage, inadequate blood flow and heart enlargement.

An electrocardiogram, often called an EKG or ECG, is a test that checks the electrical activity of your heart. This test is fast and painless. No electricity enters your body during the test. An EKG might be used if you've had chest pains, if you are being treated for a heart problem, or just as part of a regular checkup.

An electrocardiogram, also called an ECG or EKG, is a quick, painless test that measures the heart’s electrical activity and records any disturbances in heart rhythm. It transforms the heart’s electrical activity into a tracing on paper. These tracings can help determine if the rhythm of the heart is normal and can give clues whether the heart’s chambers are enlarged or under strain. Certain patterns in the ECG may also be associated with certain types of congenital heart disease.

If your doctor suspects you may have atrial fibrillation, you will likely have an electrocardiogram, known as an ECG or an EKG. This is a noninvasive test in which adhesive patches (called electrodes) are attached to your chest to detect and record the electrical activity of your heart. This test allows your doctor to see how fast your heart is beating and whether the rhythm is regular or irregular.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.