The Holter monitor is a device that records the heart rhythm continuously for 24 or 48 hours. During this time every heart beat is recorded by a cassette tape or flash card. Electrodes (sticky patches) attached to the chest are connected to wires from the Holter monitor. The monitor is carried on your person during the entire testing period determined by your physician. From the recording a variety of information can be obtained including: heart rate, abnormal heart beats, and abnormal heart rhythms. A diary is provided with the Holter monitor to record time/type of symptoms to be reviewed by your physician along with the recording. Event monitors are used to manually record heart rhythms over a longer period of time, usually a month. The patient must push a button to record an “event,” such as a rapid heart beat, etc. Recording are then transmitted over the phone to your physician for evaluation. There is no known harm/discomfort associated with the Holter or event monitors.