24 Hour ECG Holter Monitor

A 24 Hour ECG Holter Monitor measures the electrical activity of the heart over 24 hours using a lightweight monitor attached to a belt

Your doctor might recommend a 24 Hour ECG Holter Monitor for various reasons related to your heart health. Here's why you might need this test:

  • Experiencing Certain Symptoms: If you've been feeling dizzy, fainting, having trouble breathing, or feeling chest pain, a Holter Monitor can help determine if these symptoms are related to your heart.

  • Suspected Arrhythmias: Arrhythmias are conditions where your heartbeat is irregular - it might be too slow, too fast, or just uneven. If you're experiencing symptoms like palpitations (a sensation of your heart racing or skipping beats), a Holter Monitor can help detect any arrhythmias.

  • Unexplained Fainting or Near-Fainting: If you've been fainting or almost fainting (presyncope) without any clear reason, this test can help to find out if a heart condition might be the cause.

  • Pacemaker Monitoring: If you have a pacemaker and there's suspicion that it might not be working properly, a Holter Monitor can track its activity over a 24 hour period.

  • Risk Assessment After a Heart Attack: After a heart attack (myocardial infarction), your doctor might use a Holter Monitor to assess the risk of future heart-related complications.

  • Monitoring Medication Effectiveness: If you're taking medication to manage arrhythmias, a Holter Monitor can help your doctor evaluate how well the treatment is working.

  • Assessing Silent Ischaemia: Silent ischaemia is a condition where your heart muscle isn't getting enough oxygen, but it doesn't cause any noticeable symptoms. After an exercise stress test or stress echocardiogram, your doctor might use a Holter Monitor to evaluate the severity and frequency of silent ischaemia episodes.

A 24 Hour ECG Holter Monitor is a portable device that records the electrical activity of your heart continuously for 24 hours. It's like wearing a mobile heart monitoring system on your belt. It uses 4 leads that are attached to your chest to capture this information.

Before the Test

When you arrive for the test, a technician will fit the 24-hour Holter Monitor on you. You should take a bath or shower before this appointment, as you won't be able to do so while wearing the monitor for the next 24 hours.

During the Test

The actual fitting of the monitor will take about 15 minutes. Here's what you can expect:

  1. The technician will gently clean and scrub your skin where the electrodes will be placed. This usually involves using rough paper and an alcohol wipe.

  2. 4 to 5 electrodes will be attached to your chest. These electrodes are sticky patches that pick up the electrical signals from your heart. They're connected by wires to the Holter Monitor. For men, if chest hair is present in these areas, a small amount may need to be shaved off to ensure the electrodes stick properly.

  3. The monitor itself is small and light. It will be placed in a pouch that you can wear under your clothes.

Living with the Monitor

Once the monitor is fitted, you're free to go about your normal routine for the next 24 hours, with a few exceptions. You should avoid activities where the wires could get tangled or the monitor could get wet, like working with certain machinery or swimming.

During the monitoring period, if you experience any symptoms like chest pain, shortness of breath, or dizziness, there's an event button on the monitor you can press. It's important to also write down these symptoms and what you were doing at the time in a diary provided with the monitor.

After the Test

After 24 hours, you'll remove the monitor and place it, along with the diary, back into the pouch. Then, you'll return these items as directed by your healthcare provider.


While the 24 Hour ECG Holter Monitor test is generally safe and non-invasive, there are a few minor potential risks associated with it.

  1. Skin Irritation: The process of cleaning and sterilising your skin for electrode placement may cause a slight stinging sensation and leave some red patches on your skin. This is a common reaction and should clear up on its own within a couple of days.

  2. Possible Allergic Reaction: In rare cases, some patients with particularly sensitive skin may develop small blisters due to the gel used on the electrodes. If this happens, it's important not to panic. These blisters should heal quickly on their own. If you notice such a reaction and it causes you concern, please let your doctor know.

(This test will take up to 15-30 minutes)

Before you come in for your 24 Hour ECG Holter Monitor test, there are a few steps you can take to prepare:

  1. Personal Hygiene: Make sure you shower or bathe before coming in for your appointment. You won't be able to shower while you're wearing the monitor for the next 24 hours.

  2. Consideration for Men: For men, please note that it might be necessary to shave some hair on your chest. This is to ensure that the electrodes for the monitor can stick to your skin properly.

  3. Security Deposit: Lastly, please bring a $50 security deposit with you to your appointment. You can pay this in cash or on a card. This is just in case the monitor is returned late or damaged. Rest assured, your deposit will be refunded to you after 24 hours, once the monitor is returned in good condition.