Holter monitor – get a 24-hour record of your heart's electrical activity
What is a Holter Monitor?
A Holter Monitor is an ambulatory electrocardiogram (EKG or ECG) that records the electrical activity of your heart while you do your usual activities. Many heart problems become noticeable only during daily activity, and a continuous 24-hour recording is more likely to detect any abnormal heartbeats that occur during these activities.
It provides a 24- to 72-hour record of the electrical signals from your heart. A continuous recorder monitors about 100,000 heartbeats in 24 hours and is likely to find any heart problems that happen with activity.
Many people have irregular heartbeats (arrhythmias) from time to time. The importance of irregular heartbeats depends on the type of pattern they produce, how often they occur, how long they last, and whether they occur at the same time you have symptoms. Because arrhythmias can occur off and on, it may be difficult to record an arrhythmia while you are in the doctor's office.
How does a Holter Monitor work?
The Holter monitor is a recording device. The monitor has a strap that you wear over your shoulder or around your waist. The Holter monitor is battery-powered and holds a regular-sized cassette tape, much like one you would use in an audio tape player. The monitor has 5 to 7 wires called leads. The leads attach to metal disks called electrodes, which you wear on your chest. These electrodes are very sensitive, and they can pick up the electrical impulses of the heart. The impulses are recorded by the Holter monitor and give your doctor a 24-hour record of your heart's electrical activity.
What should I expect?
Holter monitoring is a painless test. You will need to go into your doctor's office to be fitted for the monitor. It is a good idea to bathe before you go to the doctor's office, because once you are fitted with the Holter monitor, you cannot get it wet in the shower or bathtub.
A nurse will clean the areas with alcohol and then place the electrodes on your chest. For men, the nurse may have to shave some small areas of your chest. The electrodes stick to the skin with a gel. Sometimes, an electrode and lead wire will be taped to your chest to prevent them from moving around.
While you are wearing the monitor, you will be asked to keep a log of your daily activities: what you did and at what time. This will help the doctor figure out what you were doing during the times that there were abnormal readings. Otherwise, you can do your typical activities, except those that might get the Holter monitor wet.
At the end of the recording period (usually 24 hours), you will return to the doctor's office or hospital to have the electrodes removed, or you may be able to remove the electrodes yourself. The recorded tape will be read by computer to provide information about your heart rate, the frequency of your heartbeats, and any irregularities.