Pediatric Holter & Event Monitoring

What Is a Holter Monitor?

A Holter monitor is a device used to record your child's electrocardiogram (ECG) tracing continuously for 24 hours or longer. When symptoms such as dizziness, fainting, low blood pressure, prolonged fatigue, chest pain or palpitations (fast or irregular heartbeats) continue to occur without a definitive diagnosis obtained with a resting ECG, your child's physician may request an ECG tracing to be recorded over a long period.

The Holter monitor gives the physician a better opportunity to capture any abnormal heartbeats or rhythms that may be causing your child's symptoms, especially if they occur infrequently. Abnormal heart rhythms (arrhythmias) may be intermittent and not seen during the shorter recording times of the resting or signal-average ECG.

Why Is Holter Monitoring Necessary?

While a standard ECG provides a vital "snapshot" of your child’s heart health, many heart rhythm irregularities are unpredictable and may not occur during a brief doctor’s visit.

Holter monitoring is necessary because it provides a continuous, 24-hour window into how the heart functions during real-world activities, such as playing or sleeping. By recording every heartbeat over an extended period, the Holter monitor allows the physician to correlate your child’s specific symptoms—like dizziness or palpitations—directly with their heart’s electrical activity at that exact moment. 

This comprehensive data is essential in helping the doctor determine if your child’s symptoms are related to a heart rhythm problem or if another cause should be explored. 

How to Prepare for Holter Monitoring? 

To prepare for the Holter monitor placement, please ensure your child bathes or showers before the appointment, as the device and electrodes cannot get wet and must remain in place for the duration of the test.

Avoid applying any lotions, oils, or powders to your child’s chest or abdomen, as these can prevent the electrodes from sticking properly to the skin.

It is helpful to have your child wear a loose-fitting shirt or a button-down top to easily accommodate the lead wires and the portable monitor. 

What to Expect During Holter Monitoring?

A patch-style ECG monitor will be placed on your child's chest. This monitor is a small, water-resistant adhesive patch—about the size of a large bandage—that contains both the electrodes and the recording device in one lightweight unit. Because the monitor is worn directly on the skin, there are no long lead wires, shoulder straps, or clips needed. You will be given instructions regarding how to:

• Keep the patch attached to your child's skin
• Check the monitor for problems
• Call the doctor’s office for help
• Keep the electrodes and monitor dry by not allowing your child to take a shower or tub bath (a sponge bath is usually allowed) or go swimming
• Avoid situations where your child may perspire excessively, causing the patch to detach
• Keep a diary during the procedure, noting the date and time of day of any changes in activity and symptoms your child experiences

Once your child has been connected to the monitor and you have been given instructions, your child will be allowed to return to usual activities, such as playing and going to school, unless the physician instructs you otherwise. You will be given a telephone number to call in case one or more of the electrodes comes off or if the monitor starts beeping. After 24 hours, the Holter monitor is returned so that the data can be analyzed and interpreted by a cardiologist.

Watch the video below to learn more about preparing for a Holter monitor test: 

Keeping a Symptom Diary 

A symptom diary is one of the most important parts of the monitoring process, as it helps the cardiologist correlate your child’s heart rhythm with their physical feelings. Whenever your child experiences a symptom—such as a "fluttering" in the chest, lightheadedness, or shortness of breath—please record the exact time shown on the monitor’s clock, the specific symptom, and the activity your child was doing at that moment (e.g., "running on the playground" or "sitting quietly reading").

Even if your child is too young to describe a sensation, please note times when they appear unusually pale, tired, or fussy. This "time-stamped" record allows the physician to look at the ECG tracing for that specific minute to see if a change in heart rhythm was the cause of the symptom. 

Receiving and Understanding Holter Results 

After the monitor is returned, a pediatric cardiologist will carefully analyze the continuous ECG recording and your child’s symptom diary. You can typically expect to receive the final results within a few business days.

These results provide a clearer picture of your child’s heart health: a "normal" report means the heart maintained a healthy rhythm, while an "abnormal" report may identify specific arrhythmias, such as premature beats or heart rate fluctuations, that require further follow-up.

If no symptoms occurred during the 24-hour window, the results might be inconclusive, and your doctor may discuss using an event monitor for a longer period to ensure they capture the information needed to provide the best care for your child.