Types of Holter Monitors

Holter monitors, also known as ambulatory electrocardiograms, are used to diagnose the cause of heartbeat irregularities. While an EKG is usually used in a doctor's office or hospital, the holter monitor is portable, allowing doctors to assess ways in which a patient's heart responds to day-to-day activities. Holter monitors are useful in detection of heart problems that are not apparent on an EKG, which is short in duration, and can be helpful for patients who have a hard time getting to a doctor's office.

Continuous Recorders

• Continuous holter monitors do what their name suggests -- provide a 24- to 72-hour record of electrical signals sent from the heart and of heart rhythms. Unlike a standard EKG, which monitors 40 to 50 heartbeats for a relatively short period of time, a continuous recorder monitors roughly 100,000 heartbeats during a 24-hour period, according to WebMD. That increases the chances of uncovering heart abnormalities, particularly those that occur during activity. Holter monitors can be worn suspended from a strap around the neck or shoulder, clipped to a belt or inside a pocket. Wires connect it to electrodes affixed to the patient's chest with sticky patches. There is also an implantable variety of the continuous recorder that is embedded underneath the skin on the chest. It can be left in the chest for as long as a year.

Intermittent Recorder

• An intermittent recorder is used to track unusual heart rhythms that do not occur frequently. It can be used for a longer stretch of time than a continuous recorder. There are two kinds of intermittent recorders: The loop recorder and the event monitor. The loop recorder makes a fixed record of heartbeats. Patients press a monitor button at the onset of unusual heart activity, and the monitor records the heart's rhythm at the time the symptoms occur. The event monitor can be worn the way a watch is worn or tucked into a purse or pocket. Patients press the back of the monitor against their chests and press a button at the onset of symptoms.

Wireless

• Wireless holter monitors record the heart's electrical activity for a predetermined amount of time. Wireless monitors can be used for longer periods of time than conventional holter monitors. Wireless monitors are attached to electrodes on a patient's chest similar to other types of holter monitors; they use wireless cellular technology to automatically transmit recorded data to a physician's office or that of a company in charge of monitoring the recorded information.