Holter Monitoring
Also known as: ambulatory electrocardiogram (ECG).
What is Holter monitoring?
Holter monitoring is a test that monitors and records your heartbeat for 24 to 48 hours. It’s typically used to gain more information about an abnormal heart rhythm and determine how long and how frequently the episodes last.
What happens during the test?
A technician will attach electrodes from the Holter monitor to your chest. You will be instructed to carry the monitor with you in a pocket, pouch or attached to your waist. You may also be instructed to keep a diary of symptoms as you wear the monitor.
Is any special preparation needed?
You cannot bathe, shower, swim, have an X-ray or go near high-voltage areas or metal detectors while wearing the monitor.
What are the risk factors?
None.
Holter monitoring at Nicklaus Children’s Hospital: Medical professionals at Nicklaus Children’s Hospital use Holter monitors and a variety of other tests to diagnose and monitor potential heart conditions.
Reviewed by: Sherrie Joy A Baysa, MD
This page was last updated on: September 16, 2025 12:43 PM
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