A Holter monitor is a portable EKG that monitors the electrical activity of a person’s heart generally for 24-hours. It is most often used when the doctor suspects an abnormal heart rhythm or ischemia (not enough blood flow to the heart muscle).
If is a painless test; electrodes from the monitor are taped to the skin. Once the monitor is in place, you can go home and perform all of your normal activities (except showering). You will be asked to keep a record of any symptoms you experience and when they occur.