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Heart Disease Health Center

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Ambulatory Electrocardiogram

An ambulatory electrocardiogram (EKG or ECG) records the electrical activity of your heart while you do your usual activities. Ambulatory means that you are able to walk during the test. This type of monitoring may also be called ambulatory EKG, Holter monitoring, 24-hour EKG, or cardiac event monitoring.

Many heart problems are noticeable only during certain activities. These include exercise, eating, sex, stress, bowel movements, and even sleeping. A constant 24-hour recording is more likely to find abnormal heartbeats that occur during these activities.

Many people have irregular heartbeats (arrhythmias) from time to time. What this means depends on the type of pattern they produce, how often they occur, how long they last, and whether they occur at the same time you have symptoms. Because arrhythmias can come and go, it may be hard to record one while you are in the doctor's office.

There are several different types of ambulatory monitors. Your doctor will choose the type that works best for you and is most likely to help diagnose your heart problem.

Why It Is Done

Ambulatory EKG monitoring is done to:

  • Look for and record irregular heartbeats that come and go or happen during certain activities.
  • Find out what is causing chest pain or pressure, dizziness, or fainting. These may be symptoms of heart problems.
  • Look for poor blood flow to your heart muscle. This is called ischemia.
  • Check to see if treatment for an irregular heartbeat is working.

How To Prepare

Be sure to tell your doctor about all the medicines you take, even over-the-counter ones. Many medicines can change the results of this test.

An EKG is often used to monitor a preexisting heart problem, such as an irregular heartbeat. So make sure that your doctor has copies of any previous EKG results.

Take a shower or bath before the electrode pads are put on. You will not be able to get the pads wet during the test. Wear a loose blouse or shirt. Do not wear jewelry or clothes with metal buttons or buckles. They can affect the recording. Women should not wear an underwire bra for the same reason.

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WebMD Medical Reference from Healthwise

Last Updated: September 26, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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