Holter and Event Monitors

Also known as Ambulatory EKG or ECG, Continuous EKG or ECG, EKG Event Monitors
Holter and event monitors are small, portable electrocardiogram devices that record your heart’s electrical activity for long periods of time while you do your normal activities.

These monitors can record how fast your heart is beating, whether the rhythm of your heartbeats is steady or irregular, and the strength and timing of the electrical impulses passing through each part of your heart. Information from these recordings helps doctors diagnose an arrhythmia, or irregular heartbeat, and check whether treatments for the irregular heartbeat are working.

There are many types of monitors, such as episodic monitors, autodetect recorders, 30-day event recorders, and transtelephonic event monitors. Your doctor will decide which monitor is best for you. Most monitors have electrodes with sticky adhesive patches that attach to the skin on your chest. Some monitors and electrodes used for long-term recording may be implanted under your skin to make it easier for you to bathe and perform your daily activities. Your doctor will explain how to wear and use the monitor and tell you whether you need to adjust your activity during the testing period. You should avoid magnets, metal detectors, microwave ovens, electric blankets, electric toothbrushes, and electric razors while using your monitor. Usually, you will be instructed to keep electronic devices such as cell phones, MP3 players, and tablets away from the monitor. After you are finished using the monitor, you will return it to your doctor’s office or the place where you picked it up. If you were using an implantable recorder, your doctor will remove it from your chest.

There is a small risk that the sticky patches that attach the electrodes to your chest can irritate your skin. You may have an allergic reaction to the electrode adhesive, but the reaction will go away once the electrodes are removed. If you are using an implantable recorder, you may get an infection or have pain where the device was placed under your skin. Your doctor can prescribe medicine to treat these problems.

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