A Holter monitor is a small wearable device that track your heart’s rhythm (for 24 to 72 hours) that record your heart’s rhythm upon a doctor’s request.

A Holter monitor test is usually performed after electrocardiogram, especially if the electrocardiogram does not 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 does not capture your irregular heartbeat, your doctor may suggest a wireless Holter monitor, which can work for weeks.

Why it’s done

If you have signs or symptoms of a heart problem, such as an irregular heartbeat (arrhythmia) or unexplained fainting, your doctor may order a test called an electrocardiogram.

It is worth mentioning that your doctor may suggest you wear a Holter monitor for a day or two, even if you have not had any symptoms of an abnormal heartbeat.


Since it is a non-invasive test, there are no significant risks involved other than possible discomfort or skin irritation where the electrodes were placed. However, the Holter monitor cannot get wet. Do not swim or bathe for the entire time you are wearing your Holter monitor.

It is also essential to avoid metal detectors, magnets, microwave ovens, electric blankets, and electric razors and toothbrushes while wearing one because these devices can interrupt the signal from the electrodes to the Holter monitor. Also, keep your cellphones and portable music players at least 6 inches from the monitor for the same reason.

How you prepare

  1. Take a bath before wearing a Holter.
  2. For men, a small amount of hair may be shaved to make sure the electrodes stick.
  3. Wear comfy cloths.
  4. A technician will attach the electrode to your chest to recording your heartbeat.
  5. The electrodes are connected to a small recording device through several wires and then the device is fixed around your belt with a waist.
  6. You’ll be instructed to keep a diary of all the activities you do while wearing the monitor. It’s particularly important to record in the diary any symptoms of palpitations, skipped heartbeats, shortness of breath, chest pain or lightheadedness. You’ll usually be given a form to help you record your activities and any symptoms.
  7. Once your monitor is fitted and you’ve received instructions on how to wear it, you can leave your doctor’s office and resume your normal activities.

After the procedure

Once your monitoring period is over, you will return to the doctor’s office to have the device detached by a technician. You will then be notified of the test result over the next few days based on the information obtained. Your doctor may make a definitive diagnosis after the Holter test, or you may need additional tests.