A Holter monitor is a small, portable device that records your heart's electrical activity continuously over 24 to 48 hours, designed to catch irregular heart rhythms (arrhythmia) throughout the day.

Unlike a standard ECG (electrocardiogram) that takes a brief snapshot lasting only a few seconds, a Holter monitor follows your heart through sleep, meals, exercise, and stress, giving a much fuller picture of how it behaves in real life.

The device consists of a small recorder that snaps onto an adhesive patch placed directly on the chest. It sits flat against the skin under clothing, and you carry on with your usual routine while it quietly records in the background.

A Holter monitor is mainly used to pick up irregular heart rhythms that may not show up during a routine ECG, especially those that come and go unpredictably. By recording over a longer stretch of time, it captures brief episodes that a standard test would likely miss.

Common findings include:

• Atrial fibrillation (AFib) — an irregular, often rapid rhythm from the atria (the heart's upper chambers) that raises stroke risk.
• Pauses or skipped beats — short interruptions in the normal rhythm that can cause dizziness or fainting.
• Supraventricular tachycardia (SVT) — sudden bursts of fast heartbeats originating above the ventricles (the heart's lower chambers).
• Ventricular ectopics (VE) and tachycardia — extra or abnormal beats from the lower chambers.
• Bradycardia and heart block — abnormally slow rhythms or delays in the heart's electrical signal.
• Silent ischaemia — periods of reduced blood flow to the heart muscle that may not produce obvious symptoms.

A Holter monitor may be suggested when symptoms point to a possible heart rhythm problem but a standard ECG has not captured anything conclusive. Common situations include:

The test is non-invasive and suitable for most people, including older adults. It may not be ideal for those with significant skin allergies to adhesive patches, though hypoallergenic alternatives are often available.

The Holter monitor test is straightforward and involves fitting the device, wearing it through your daily routine, and returning it for analysis.

The whole process is painless and does not interrupt most normal activities. When symptoms are infrequent, an extended version of the monitor can record for up to 7 to 14 days.

Results are typically available within one to two weeks depending on the recording length.

Most normal activities can continue while wearing the device, with the main restriction being to keep it dry. The recorder is lightweight and sits comfortably under clothing, so most people find it easy to ignore after a short while.

A few practical points:

• Light showers are permitted — keep showers brief (10 to 15 minutes), avoid soaping the chest area around the device, and pat dry thoroughly with a towel afterwards. Baths, swimming, and prolonged water exposure must be avoided.
• Stay away from strong magnets and electrical fields — MRI scanners and high-voltage equipment can interfere with the recording. Brief exposure to metal detectors is generally fine, but prolonged contact should be avoided.
• Mark symptoms on the device — double-tap the recorder when experiencing symptoms such as dizziness or palpitations. A brief blue light confirms the event has been captured.
• Keep the diary accurate — note the time of any palpitations, chest discomfort, dizziness, or unusual symptoms so they can be cross-referenced with the trace.
• Keep the device secure — gently press the edges of the patch after changing clothes or showering to ensure it remains firmly attached. Sleep on the back or side if possible.
• Avoid vigorous exercise and upper body massage — light to moderate activity is encouraged, but intense physical activity may loosen the patch or affect the recording.
• Avoid necklaces — jewellery around the neck may interfere with the device during the recording period.

Mild skin irritation or redness under the pads is common and typically settles within a few days of removing the device.

A Holter monitor and an ECG measure the same electrical signals, but they differ in how long they record and what kind of problem they are best suited to catch. The table below compares the most common tests used to investigate heart rhythm and function.

Preparation for a Holter monitor test is minimal, and no fasting or medication changes are usually required unless your doctor has advised otherwise. A few small steps help the patch stay in place.

• Shower beforehand for comfort, though light showers are permitted during the recording period.
• Wear a loose-fitting top on the day of fitting for easy access to the chest.
• Avoid applying lotions, oils, powders, or perfumes to the chest area.
• Keep taking usual medications unless told otherwise, and bring a list of them to the appointment.

Holter monitor results are reported as either normal, showing expected variations in heart rate, or abnormal, where specific rhythm disturbances are identified and quantified.

Your doctor will correlate findings with the symptom diary to decide whether further tests, lifestyle changes, or treatment are needed.

At ATA Medical, we offer the Holter monitor test, alongside other heart tests, with prices as follows:

*Prices are NETT and inclusive of GST.
^Prices last updated on Apr 29, 2026. While every effort is made to keep pricing information up to date, please contact our team to confirm the latest rates.

You may also wish to explore our heart check-up or health screening packages, which bundle several of these tests for a more complete assessment.

• Tanjong Pagar Clinic
• Orchard Clinic
• Jurong Clinic
• Novena Clinic