A Holter monitor is a small, portable device that monitors and records the electrical rhythms of your heart via an electrocardiogram (ECG) over an extended period of time, usually over 24 or 48 hours.

It provides information about how the changes in your heart rhythm correspond with your daily activities and sleep patterns and it is used to investigate a range of symptoms such as dizziness or palpitations.

Having a monitor fitted is straightforward. Follow our step-by-step guide below to know what to expect. Alternatively, you can download our Holter monitor patient brochure here.

 Note: if whilst the Holter monitor is being worn, contact your GP or relevant health care professional if you:

• feel faint or dizzy
• develop a rash or redness on the skin

or if you experience:

• heart palpitations
• chest pain
• extra beats
• shortness of breath

What are the risks of Holter monitors?

Wearing a Holter monitor has no risks and causes no pain. Holter monitors have wires that connect to small discs (electrodes) attached to your chest to record the electrocardiogram. Because the electrodes are attached with tape or adhesives, they may cause mild skin irritation. Tell the technician if you are allergic to any tapes or adhesives.