Facebook Twitter Instagram You Tube Pinterest LinkedIn RSS Podcasts Video Library Blog
 - Northwestern Memorial Hospital - Chicago

Event Monitor

The Cardiac Event Monitor is used to detect abnormal heart rhythms. This small device records the heart's electrical activity (rhythm) at the push of a button. Patients trigger the device when they first begin to feel signs (an "event") such as:

  • Dizziness
  • Weakness
  • Lightheadedness
  • Heart racing and/or fluttering

The monitor stores the heart rhythm. Later that rhythm is sent via the telephone to the doctor for review. This test allows for on-demand heart monitoring outside the hospital/clinic setting when symptoms are noted and as you go about your normal routine. The test results help guide your doctor to choose treatment options to meet your specific needs.

The monitor, about the size of a deck of cards, is clipped to your waistband. This monitor is connected to a set of wires which attaches to two electrodes worn on your chest (like an EKG). The monitor can be worn for up to 30 days. It is removed during bathing.


Follow the tech's guidelines for transmitting recordings. This can be done daily, weekly or whenever you feel your symptoms need immediate attention. In most cases, it is important to transmit after three or four "events" (due to the monitor's limited storage capacity).

Recordings cannot be transmitted by cell phone or any other portable phone. Should the findings indicate that you need medical care, your doctor will be notified right away.

Removing the Monitor

Remove the monitor as instructed. Return the monitor, wires, unused electrodes and batteries, and your diary to the Cardiac Stress Testing/Heart Monitoring Department or Clinic.

Your final test report will be sent to your doctor after the monitor is returned and all the recordings have been reviewed by a cardiologist. A full report will be sent/faxed to your doctor.


For more information regarding the Bluhm Cardiovascular Institute, please call 1-866-662-8467 or request an appointment online.

Last UpdateMarch 16, 2011