A Holter monitor is a device you wear that records your heart’s electrical activity for 24 to 48 hours. You wear the Holter monitor while you do your daily activities. If you have an irregular heartbeat or heart palpitations but an EKG didn’t detect anything, a cardiac monitor can help diagnose the problem.
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A Holter monitor (heart monitor) is a wearable device and a type of ambulatory electrocardiogram (EKG). It records your heart’s rhythm and rate for 24 to 48 hours without breaks. This gives your provider a long look at your heart’s electrical activity as you go about your day.
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This monitor is small (about the size of a deck of playing cards), lightweight and runs on battery power. It has wires and electrodes (small patches) that stick to your skin. While you wear a Holter monitor under your clothes, you continue with your regular daily activities.
The Holter monitor gets its name from Dr. Norman J. Holter, who created it in the 1950s.
Like an electrocardiogram (EKG), a Holter monitor gathers information about your heart’s electrical activity. But instead of wearing it for a few minutes like an EKG, you wear a Holter heart monitor for a full day or two. This allows more chances to pick up unusual activity.
A Holter monitor can help if an EKG doesn’t provide clear results. It can find the cause of:
Your provider can also use a cardiac monitor to determine how well your heart medications are working.
Electrodes (stickers) on your chest sense your heart’s electrical activity. They send this information through wires to the Holter heart monitor in your pocket or elsewhere on your body. The monitor records this data for later. Providers don’t monitor your device as it records information. They access the collected data after you turn in your device.
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You don’t need to do anything special on your own to prepare for a Holter monitor. You’ll probably want to shower or bathe before putting on the device. You won’t be able to get the monitor wet when you’re wearing it.
A provider will get you set up and then you can go about your normal day. They’ll:
You can do most of your usual activities — even sleeping — while you wear a Holter heart monitor.
But while wearing your cardiac monitor, you should avoid:
After the 24- or 48-hour period:
Note: A medical professional doesn’t continually monitor the findings of this test. Seek medical care if you develop symptoms.
Wearing a Holter heart monitor doesn’t involve any risks or pain. Some people might have itchiness or irritation from the tape that attaches the electrodes to your chest.
Let your provider know if you have any allergies to tapes or adhesives.
The results may show that the Holter monitor detected a heart rhythm disorder (arrhythmia), like:
Your provider will contact you with the results within a week or two after the test.
Your provider will discuss the next steps with you. They may recommend:
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Contact your provider if:
Please note that a medical professional isn’t continually monitoring the findings of this test. You should seek medical care if you develop symptoms.
If anxiety is causing you to have heart palpitations, a Holter monitor can record them. Your provider will need to analyze the recording to see what kind of palpitations you had. It may be helpful to write down what you’re doing and feeling when you have palpitations.
An EKG measures your heart’s activity at that moment in time, as you’re having the test. But your heart’s rhythm and symptoms can change throughout the day.
Your provider may want to see how your heart’s rhythm changes during the day as you do your regular activities. The heart monitor gives your provider a more complete picture of your heart rhythm.
A Holter monitor records your heart rhythm continuously for 24 or 48 hours. An event monitor isn’t continuous. It only records your heart’s activity when you feel symptoms and activate the monitor.
What’s causing your heart flutters, racing heart or dizziness? Not knowing the cause is frustrating. A Holter monitor may help you find out. While it may take a little getting used to, this small, painless device is something you only wear for a day or so. After that, you’re one step closer to a diagnosis and feeling better.
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Last reviewed on 04/14/2024.
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