Holter Monitor

A Holter monitor is a small, wearable device that keeps track of your heart rhythm. Your doctor may want you to wear a Holter monitor for one to two days. During that time, the device records all of your heartbeats.

A Holter monitor test may be done if a traditional electrocardiogram (ECG) doesn’t give your doctor enough information about your heart’s condition.

Your doctor uses information captured on the Holter monitor to figure out if you have a heart rhythm problem. If standard Holter monitoring doesn’t capture your irregular heartbeat, your doctor may suggest a longer-term monitor, which can record your heartbeat over several weeks.

Some personal devices, such as smartwatches, offer electrocardiogram monitoring. Ask your doctor if this is an option for you.

Why it’s done

Your doctor may recommend that you wear a Holter monitor for a day or so if you have signs and symptoms of an irregular heart rhythm (arrhythmia) or unexplained fainting.

Before you get a Holter monitor, you’ll have an electrocardiogram (ECG). An ECG is a quick and painless test that uses sensors (electrodes) taped to your chest to check your heart’s rhythm.

However, sometimes an ECG doesn’t detect any changes in your heart rhythm because you’re hooked up to the machine for only a short time. A Holter monitor may be able to spot occasionally abnormal heart rhythms that an ECG missed.

A Holter monitor test may also be done if you have a heart condition that increases your risk of an abnormal heart rhythm.