A holter monitor is a small portable battery powered device that continuously records the hearts activity such as heart rate and rhythm over a period of time (usually 24-48 hours). The actual monitor is slightly smaller than a standard deck of cards and has 7 electrodes that will attach to your chest. A small pouch holds the monitor itself which can attach to the waistband of your pants, on a belt or on a strap around your neck.
Holter monitoring is used to help explain what is happening to your heart rhythm and/or why you are having palpitations. The monitor may also be use