Holter Monitoring: About This Test

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What is it?

A Holter monitor is a small machine that records the electrical activity of your heart. You wear it for 24 to 48 hours while you do all your normal activities.

The monitor has wires that attach to small electrode pads. These pads are taped to your chest.

This kind of machine has many different names. It is sometimes called an ambulatory monitor, an ambulatory electrocardiogram, or an ambulatory EKG. It can also be called a 24-hour EKG or a cardiac event monitor.

Why is this test done?

You may have this test to find out if you have a problem with your heart. Many heart problems can only be noticed when you are doing something. They may happen when you exercise, eat, have sex, or sleep. Or they may happen when you have a bowel movement or you feel stressed. Your Holter monitor will record the way your heart beats during all of these activities.

Holter monitoring also will:

  • Look for what may cause chest pain, dizziness, or fainting.
  • Check to see if treatment for an irregular heartbeat is working.

How can you prepare for the test?

  • Before the test, talk to your doctor about all your health problems. Tell him or her about all the medicines and vitamins you take.
  • Take a shower or bath before the pads are put onto your chest. You must not get the pads wet during the test.
  • Wear a loose blouse or shirt.
  • Do not wear jewellery or clothes with metal buttons or buckles.
  • If you are a woman, do not wear an underwire bra.

What happens before the test?

  • Areas of your chest may be shaved and cleaned.
  • The electrode pads are attached to your chest with a paste or gel.
  • You wear the monitor on a strap over your shoulder or around your waist. It uses batteries and does not weigh much.

What happens during the test?

  • You need to record your activities and symptoms. You will write down the time your symptoms started. And you will write down what type of activity you were doing.
  • You can use the clock on the monitor to help you keep track of the time your symptoms started.
  • When you sleep, try to stay on your back with the monitor at your side. This will prevent the pads from coming off.

What else should you know about the test?

  • When you wear the monitor, try to stay away from magnets, metal detectors, high-voltage areas, garage door openers, microwave ovens, and electric blankets.
  • Do not use an electric toothbrush or shaver.
  • The pads may make your skin itch a little. And your skin may look or feel irritated after the pads are removed.

How long does the test take?

  • You usually wear the monitor for 24 to 48 hours.

What happens after the test?

  • You may return to the doctor's office or hospital to have the pads removed. Or you may be able to take them off yourself.
  • You will return the Holter monitor to your doctor's office or hospital.
  • You can go back to your usual activities right away.

Where can you learn more?

Go to https://www.healthwise.net/patientEd

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