Holter Monitors

Holter Monitors: What You Need to Know

What is a Holter Monitor?

A Holter monitor is a small, portable device that continuously records your heart’s electrical activity, usually over 24 to 72 hours. It’s similar to an ECG (electrocardiogram), but it works while you go about your normal daily activities, including sleep.

This allows doctors to monitor your heart rhythm over a longer period and catch any irregularities that might not appear during a short ECG in a clinic.

Why Would I Need a Holter Monitor?

Your doctor may recommend a Holter monitor if you experience symptoms such as:

  • Irregular heartbeats (palpitations)

  • Dizziness or fainting

  • Unexplained chest pain

  • Shortness of breath

  • Fatigue or weakness

A Holter monitor can help diagnose conditions like:

  • Arrhythmias (irregular heart rhythms)

  • Bradycardia (slow heart rate)

  • Tachycardia (fast heart rate)

  • Atrial fibrillation

  • Unexplained symptoms possibly related to heart rhythm issues

It’s also sometimes used to check how well treatments like medications or pacemakers are working.

What to Expect When Wearing a Holter Monitor

  • Setup: Small sticky patches (electrodes) will be placed on your chest and connected to the monitor with wires.

  • Wearing it: You’ll carry the device with you, often clipped to a belt or worn in a pouch.

  • Duration: Most patients wear it for 24 to 72 hours, depending on what your doctor recommends.

  • Activity log: You may be asked to keep a diary of your symptoms and activities during the monitoring period.

Tip: Continue your normal routine while wearing the monitor, unless your doctor advises otherwise. This helps capture real-life heart activity.

How is the Data Analysed?

Once your monitoring period is complete:

  1. The monitor is returned to the clinic or hospital.

  2. The data is downloaded and reviewed by a cardiac technician and your doctor.

  3. The recorded electrical signals from your heart are checked for any irregular patterns.

  4. Your activity diary is compared to the data to see if symptoms match any abnormal heart rhythms.

Your doctor will then discuss the results with you and decide on the next steps, whether it's further testing, treatment, or reassurance that your heart rhythm is normal.

Wondering if you need a Holter Monitor in London?

If you have a family history of heart disease or have been advised to undergo genetic testing, speak to our specialists at London Heart Group.
Get a comprehensive cardiac assessment at London Heart Group. Call us on 0208 226 5888 or email enquiries@londonheartgroup.co.uk

Protect your heart. Protect your family. Get answers with our expert cardiologists.