A Holter monitor is a small, battery-powered medical device that measures a patient’s heart activity, such as rate and rhythm, for 24 hours, to monitor the functioning of the heart over a period of time. Holter monitor testing is also called ambulatory electrocardiography. The patient is required to wear the Holter monitor for 12 to 48 hours as they go about their daily routine.
This device is almost like a regular ECG with electrodes and electrical leads, just fewer leads. It can not only pick up heart rate and rhythm, but can also pick up changes during chest pains like irregular heartbeat or arrhythmia. The recordings can help the doctor determine if the patient’s heart is getting enough oxygen or if the electrical impulses in the heart are delayed or early.