Holter Monitoring Test

What is a Holter monitoring test?

A Holter monitoring test is a non-invasive diagnostic test. In general, it uses a portable device called a Holter monitor to continuously record your heart's electrical activity for 24 – 48 hours. Depending on your condition and Holter device, your doctor may also recommend using the device for up to 1 week.

This monitoring period differs from an electrocardiogram (ECG), which only records the heart's electrical activity for a short period.

holter-monitor

Why do you need a Holter monitoring test?

Your doctor may recommend a Holter monitoring test to:

Detect transient (temporary) rhythm disorders of the heart. The test allows your doctor to correlate symptoms such as palpitations (fast, strong, or irregular heartbeats, fainting and dizziness spells to your heart rhythm.
Monitor the electrical activity of your heart during normal activity or after a heart attack.
Diagnose any abnormal heart rhythm (including serious arrhythmias).
Determine the success of a heart procedure.
Monitor the effect of new heart medicine.

What are the risks and complications of a Holter monitoring test?

There is no significant risk from wearing a Holter monitor. You may feel some discomfort from wearing the device continuously or skin irritation where the electrodes are attached.

How do you prepare for a Holter monitoring test?

In general, the Holter monitor needs to stay dry to prevent damage to it. Some of the modern Holter devices, such as patch Holter monitors, can support light showers and even swimming.

You may wish to take a shower before your scheduled appointment to attach the device.

What can you expect in a Holter monitoring test?

You can carry on with your normal activities during the test.

Estimated duration

In general, you may need to wear the device for 24 – 48 hours. Depending on your condition and Holter device, your doctor may recommend wearing the device for up to 1 week.

Before the procedure

Your doctor will attach the small sensors (electrodes) to your chest. A small amount of hair may need to be shaved to allow the electrodes to stick to your skin better.

The sensors will be connected to a recording device with a few wires. Your doctor will instruct you on how to wear the recording device so that it works properly.

During the procedure

You will wear the Holter monitor throughout the duration of the test, including when you are asleep. You need to keep a record of your activities and note down any of these symptoms:

Any pounding, fluttering or skipped heartbeats
Shortness of breath
Lightheadedness
Chest pain

After the procedure

Return the device to your doctor, together with your record of symptoms. Your doctor will study the readings of the Holter monitor against your physical daily activity to determine any abnormal heartbeats and disorders.

Frequently asked questions

A: A Holter monitor measures the electrical activity of your heart continuously for usually 2 days, sometimes up to a week. In contrast, an electrocardiogram (ECG) measures the electrical activity of your heart for a short period.

An extended monitoring period allows your doctor to:

Monitor your heart’s electrical activities after heart procedures or the use of new medication.
Detect abnormal heart rhythms disorders such as atrial fibrillation, bradycardia, tachycardia or premature ventricular contractions (PVCs).

Your doctor will explain the results of your Holter monitoring test to you. In general, the results should indicate your:

Average heart rate
Fastest and slowest heart rate
Heart's pauses and their duration
Fast heart rhythms and their characteristics

A: A Holter monitor cannot detect blockages in the heart vessels. However, your doctor may use your Holter monitor results and diary to determine if any abnormal readings or palpitations might be related to:

Heart arrhythmia
Sleep apnoea
Anxiety

The Holter can help to diagnose heart arrhythmias if they are present during the monitoring period. Conversely, if palpitations were experienced during the monitoring period but there were no objective arrhythmias, the Holter can help rule out any significant cardiac arrhythmias. Such palpitations may be due to stress or anxiety instead.

Further tests may be needed to confirm the diagnosis and treatment.

A: No, a Holter monitor records the electrical activity of your heart, not blood pressure.

Blood pressure is measured through a conventional blood pressure monitor or ambulatory 24-hour blood pressure monitor.

A: Yes, when worn and used properly, Holter monitors can accurately record your heart's electrical activities.

A: Yes, you can wear a bra with a Holter monitor.

However, try not to remove your bra for the entire monitoring duration to avoid dislodging the leads or electrodes attached to your body.

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