What is a Holter Monitor?

A Holter monitor is a electrocardiography device which is designed to be worn by an ambulatory patient. Worn for periods of time which can vary between one and three days, the Holter monitor creates a continuous record of a patient's heart rhythm which can be used as a diagnostic tool. These devices are used in the diagnosis of patients who have irregular arrhythmias or who report transient heart problems, because these problems are usually hard to detect with an in-hospital electrocardiography session.

Named for Dr. Normal Holter, the device consists of a box which is worn on the belt and attached to electrodes on the chest. The Holter monitor is designed to be used continuously, with some models being wearable in the shower, and it is relatively comfortable to wear, although some people find the electrodes and wires restrictive. Holter monitors are entirely painless. While wearing a Holter monitor, a patient may be asked to keep an activity log which can be compared with the device's reading.

Once the patient is done wearing the Holter monitor, the information can be analyzed by a doctor or cardiologist to learn more about the patient's condition. Treatment recommendations may be made, or a doctor may take a wait and see approach to see if cardiac arrhythmias become more severe or more frequent. The record also goes into the patient's chart so that it can be referenced in the future.

Typically a patient is given a brief orientation session with the Holter monitor, in which a doctor or nurse shows the patient how the monitor is used. The patient is given spare electrodes to use in the event that the monitor needs to be removed, and is reminded that if a serious cardiac event occurs, the patient should go to a hospital for treatment. Patients are also encouraged to exercise as they normally would and to keep their schedules normal so that the monitor provides an accurate picture of the patient's health.

As an alternative to a Holter monitor, a patient may be given an event monitor. Event monitors are worn continuously like Holter monitors, but they only start recording when they are specifically activated. These monitors can be worn for much longer periods of time, and are used for patients who complain of specific cardiac events which are easy to recognize, giving the patient time to active the monitor to record heart rhythm.