The Holter monitor is a type of portable electrocardiogram (ECG). It records the electrical activity of the heart continuously over 24 hours or longer while you are away from the doctor’s office. Electrodes (small, plastic patches that stick to the skin) are placed at certain points on the chest and abdomen. The ECG electrode patches are placed on your chest, and the electrodes are connected by wires to a small, portable recording device. Then, the electrical activity of the heart can be measured, recorded, and printed.
Holter monitor may be advised if you have symptoms, such as dizziness, fainting, low blood pressure, ongoing fatigue (tiredness), and palpitations and a resting ECG doesn’t show a clear cause. Certain arrhythmias (abnormal heart rhythms) may occur only now and then. Or, they may occur only under certain conditions, such as stress or activity. Arrhythmias of this type are hard to record on an ECG done in the office. Because of this, a Holter monitor has a better chance of capturing any abnormal heartbeats or rhythms that may be causing the symptoms.