Holter monitoring

A Holter monitor is used to assess your heart rate and rhythm for 24 hours or longer. It can help to identify abnormal heart rates or rhythms (arrythmia).

What is Holter monitoring?

A Holter monitor records your heart rate for a specific length of time, to identify an abnormal rhythm.

It's usually worn for 24 hours, 48 hours, 72 hours or up to five days.

You can go about your daily activities wearing the monitor. A doctor later analyses the information when you've stopped wearing it.

Your consultant may ask you to wear a Holter monitor if you're having symptoms such as dizziness, palpitations and breathlessness.

The monitor is often used when an ECG fails to pick up an issue.

How is a Holter monitor fitted?

A cardiac physiologist (a specialist who carries out cardiac tests) will fit the Holter monitor for you.

Three electrodes will be placed on your chest. Leads will connect them to the device, which is about the size of a mobile phone.

You can keep the device in your pocket or bag and go about your normal routine. You will need to remove the monitor when you bathe. The physiologist will show you how to do this.

Fitting the device should take around 20 minutes.

What happens afterwards?

When you've finished wearing the monitor for the specified time, you're free to remove it yourself. Please return it to us at your earliest convenience.

Data will be downloaded from the device and analysed.

Your results will be sent to the consultant who requested the test and discussed with you at your next appointment.

How to prepare for a Holter monitoring

You don't need to do anything specific to prepare.

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Disclaimer: This information is published by Cromwell Hospital and is based on reputable sources of medical evidence and experience from over 30 years of treating patients. It has been peer reviewed by Cromwell Hospital doctors. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional. If you have any feedback on the content of this patient information document please email info@cromwellhospital.com or telephone 020 7460 5901.