A Holter monitor is a portable device used to continuously record the heart’s electrical activity (ECG) over a period of 24 to 48 hours, or sometimes longer. It typically consists of electrodes placed on the chest, which are connected to a small recording device worn by the patient. The Holter monitor records the ECG signals throughout the monitoring period, capturing any abnormal heart rhythms or patterns that may occur during daily activities.

After the monitoring period, the recorded data is analyzed by a cardiologist to assess the heart’s function and detect any potential abnormalities.