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.) Ambulatory monitors
are referred to by several names, including ambulatory electrocardiogram,
ambulatory EKG, Holter monitoring, 24-hour EKG, or cardiac event monitoring.
Many heart problems become noticeable only during activity, such as
exercise, eating, sex, stress, bowel movements, or even sleeping. A continuous
24-hour recording is more likely to detect any abnormal heartbeats that occur
during these activities.
Many people have irregular heartbeats (arrhythmias)
from time to time. The importance of irregular heartbeats 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 occur
off and on, it may be hard to record an arrhythmia while you are in the
There are several different types of ambulatory monitors. Your doctor will choose the type that is most appropriate 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
occur intermittently or during certain activities.
- Find out what is
causing chest pain, dizziness, or fainting. These are symptoms of possible
- Look for poor blood flow to your heart muscle
- Check to see if treatment for an irregular heartbeat is
How To Prepare
Many medicines may change the results of this test. Be sure to tell
your doctor about all the nonprescription and prescription medicines you
Since an EKG is often used to monitor a preexisting heart
condition, such as an irregular heartbeat (arrhythmia), make sure that your
doctor has copies of any previous EKG results.
Take a shower or bath before the discs are put on. You will not be
able to get the discs wet during the test. Wear a loose blouse or shirt. Do not
wear jewelry or clothes with metal buttons or buckles, because these can
interfere with the recording. Women should not wear an underwire bra for the
If your doctor asks you to keep a symptom and activity diary, be sure you have a method. In this diary, you will record activities and symptoms and the times they occurred. The accuracy and usefulness of your test depend on how carefully you keep this record.
If you are getting a monitor implanted under your skin, you will receive instructions on how to prepare for the procedure.
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?).