Event Monitor

What Is an Event Monitor?

An event monitor is a portable heart rhythm recorder that you wear for days to weeks at a time. Unlike a Holter monitor that records continuously, some event monitors only record when you press a button because you’re feeling symptoms, while others record continuously and automatically flag unusual rhythms. This extended monitoring period is ideal for catching problems that happen infrequently.

Why Is It Done?

Your doctor may recommend an event monitor if you have occasional symptoms (like palpitations, dizziness, or fainting) that happen too infrequently to be captured by a 24- to 48-hour Holter monitor. It’s a valuable tool when your doctor suspects an irregular heart rhythm but hasn’t been able to document it yet. The longer you wear the monitor, the better the chance of catching an episode.

What to Expect

Depending on the type of monitor, small electrode patches will be placed on your chest, or you’ll wear a small device on your wrist or chest. You’ll take the monitor home and wear it during all your normal activities, including sleep. If you feel symptoms, you may press a button to mark the recording. Some monitors transmit data automatically to your doctor’s office. The monitoring period typically lasts 1 to 4 weeks.

How to Prepare

Shower before your appointment, as some monitors cannot get wet (your care team will explain the specific instructions for your device). Avoid applying lotion or cream to your chest. Wear comfortable clothing, and plan to keep the monitor on at all times, including while sleeping. Continue taking all your medications as prescribed.