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The Heart Care CenterDr. Ashish Chauhan
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Also called 24-hour ECG, Ambulatory ECG, Heart rhythm monitor

Holter monitoring

A small ECG recorder worn under your clothes for a day or more, so that a rhythm disturbance which comes and goes can be captured while you go about ordinary life.

How long
Worn 24 to 72 hours
Preparation
Clean, dry skin. No lotion
Does it hurt
None, though the electrodes can itch
Results
Reported after the recording is analysed
A small white Holter monitor about the size of a matchbox, with a screen showing a live ECG trace and four coloured electrode leads coiled beside it.
The recorder is roughly the size of a matchbox and is worn under clothing. The leads clip to electrodes on the chest; the screen is used to check signal quality when it is fitted, not to be read by you.Photograph: Tristaess, via Wikimedia Commons (public domain).

What happens

  1. 01

    Electrodes and a small recorder are fitted

    Three to seven stickers on the chest connect to a recorder about the size of a phone, worn on a strap or clipped to clothing.

  2. 02

    You go home and live normally

    That is the point of the test. Ordinary activity, work and sleep are what the recording needs to capture.

  3. 03

    You keep a symptom diary

    Note the clock time of any palpitation, dizziness or chest discomfort, and what you were doing. This is what allows symptoms to be matched to the trace.

  4. 04

    You return the device and the recording is analysed

    Software scans every beat and a doctor reviews the significant sections against your diary.

What it shows

  • The heart rhythm continuously, across sleep, activity, meals and stress
  • Episodes of atrial fibrillation, including episodes causing no symptoms at all
  • How frequent extra beats are, and whether they cluster or occur in runs
  • Pauses in the rhythm, and how long they last
  • Whether the symptoms you record in your diary actually coincide with a rhythm abnormality — often the single most useful output
  • Heart rate range across the day, and its response to exertion and sleep

What it cannot tell you

  • If no episode occurs while the monitor is on, the recording will be normal. That does not prove nothing is wrong; it means it was not caught, and a longer monitor may be arranged.
  • It records rhythm only. It does not assess pumping function, valves or the coronary arteries.
  • Electrodes occasionally lift, producing artefact that can look alarming but is a recording issue rather than a cardiac one.

How to prepare

  • Shower before the monitor is fitted, because you cannot bathe while wearing most recorders.
  • Do not apply oil, lotion or powder to the chest that day.
  • Wear loose two-piece clothing for the duration.
  • Keep the diary in real time. Written afterwards from memory, it loses most of its value.
  • Do not avoid the activities that usually trigger your symptoms — provoking them during the recording is what makes the test work.

Conditions this helps assess
Other tests

Book a consultation

Tests are arranged after an assessment, so that each one is answering a question that matters in your case.

Book an appointment
Clinic
13, Ground Floor, M.K. Plaza, Hospital Road, near Madhav Dispensary
Gwalior 474001
Directions
OPD hours
Monday to Saturday
12:30–2:30 pm, 5:30–6:30 pm
Closed Sunday
In an emergency
Do not use this site. Call 108 for an ambulance or go to the nearest emergency department.