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Holter Monitor

What is a Holter monitor?

A Holter monitor is a type of portable electrocardiogram (ECG). It records the electrical activity of the heart continuously over 24 hours or longer while you are away from the healthcare provider’s office. Most monitors come in patch form which stick to the upper left portion of your chest. Monitors are typically worn between 24 hours and 30 days depending on the condition of the patient and the provider’s recommendation.

Why might I need a Holter monitor?

Some reasons your healthcare provider may ask for a Holter monitor recording or event monitor recording include:

  • To evaluate symptoms that may be heart-rhythm related. Symptoms can include e chest pain, tiredness, shortness of breath, dizziness, or fainting.
  • To identify irregular heartbeats or palpitations.
  • To assess your risk for future heart-related events in certain conditions. These conditions can include thickened heart walls (hypertrophic cardiomyopathy) after a heart attack that caused weakness of the left side of the heart. This is called Wolff-Parkinson-White syndrome. In this syndrome, an abnormal electrical conduction pathway exists in the heart.
  • To see how well a pacemaker is working.
  • To find out how well treatment is working for complex abnormal heart rhythms;
  • To see how fast or slow your heart rate gets during the day. And to see if you have any pauses in your heart rhythm.

Your healthcare provider may have other reasons to advise a Holter monitor.

What are the risks of a Holter monitor?

The Holter monitor is an easy way to check the heart’s function. Risks of a Holter monitor are minimal and rare.

It can be hard to keep the electrodes stuck to your skin. Extra tape may be needed. It may be uncomfortable when the sticky electrodes and tape are taken off. If the electrodes are on for a long time, they may cause skin irritation or blistering.

There may be other risks depending on your specific health condition. Talk to your healthcare provider about any concerns before wearing the monitor.

Some factors or conditions may affect the results of the Holter monitor reading. These include:

  • Being near magnets, metal detectors, high-voltage electrical wires, and electrical appliances. Appliances can include shavers, toothbrushes, and microwave ovens. Cell phones can also interfere with the signals. Keep them at least 6 inches away from the monitor box.
  • Excessive sweating, which may cause the leads to loosen or come off

How do I get ready for a Holter monitor?

  • Your healthcare provider will explain the procedure and you can ask questions.
  • You don't need to fast (not eat or drink).
  • Your healthcare provider may have other instructions for you.

What happens during a Holter monitor?

A Holter monitor recording is generally done on an outpatient basis. Procedures may vary depending on your condition and your healthcare provider's practice.

Generally, a Holter monitor recording follows this process:

  1. You will be asked to remove any jewelry or other objects that may interfere with the recording.
  2. You will be asked to remove your clothing from the waist up so that electrodes can be attached to your chest. The technician will ensure your privacy by covering you with a sheet or gown and exposing only the necessary skin.
  3. The area where the patch will be placed is cleaned, and in some cases, hair may be shaved or clipped so that the patch will stick closely to the skin.
  4. Once the patch has been placed, you can return to your usual activities unless your healthcare provider tells you otherwise.
  5. You may be told to keep a diary of your activities while wearing the monitor. Write down the date and time of your activities, particularly if any symptoms, such as dizziness, palpitations, chest pain, or other previously experienced symptoms, occur.

What happens after a Holter monitor?

You should be able to go back your normal diet and activities unless your healthcare provider advises differently.

Usually, there is no special care after a Holter monitor recording.

Tell your healthcare provider if you have any symptoms you had before the recording. For instance, if you have chest pain, shortness of breath, dizziness, or fainting.

Your healthcare provider may give you other instructions after the procedure.

Next steps

Before you agree to the test or the procedure make sure you know:

  • The name of the test or procedure
  • The reason you are having the test or procedure
  • What results to expect and what they mean
  • The risks and benefits of the test or procedure
  • What the possible side effects or complications are
  • When and where you are to have the test or procedure
  • Who will do the test or procedure and what that person’s qualifications are
  • What would happen if you did not have the test or procedure
  • Any alternative tests or procedures to think about
  • When and how you will get the results
  • Who to call after the test or procedure if you have questions or problems
  • How much you will have to pay for the test or procedure