What is a Holter monitoring?

ECG, Electrocardiogram takes a snapshot of the electrical activity of the heart over say 5 seconds. What about getting an ECG for 24 hours. Heartbeats for approximately 1 lac time a day. How to pick up ECG abnormality occurring during sleep? The answer is Holter monitoring. We apply a small electrode over chest attached to a small battery containing device which keeps recording activity for 24 to 48 hours.

24 hour Holter monitoring is a continuous record of your heart’s rate and rhythm for the entire day and night.n You wear the Holter monitor for 12 to 48 hours as you go about your normal daily routine. Most of the device does have a trigger button which you can press when you feel any symptoms.

This is not an event recorder or ELR ( event loop recorder ). ELR is implanted below the skin and destined to be there for months.

When any patient needs Holter monitoring 

  • Any patient with a history of episodic palpitations, episodic fast heart rate, but his ECG is normal
  • patient with a history of blackout also called syncope
  • stroke patient
  • patient with atypical seizure/convulsion like episodes.
  • to see the medicine response and effectiveness of medicine in controlling the abnormal rhythm.

Episodic palpitation or fast heart rate can occur for few seconds to few minutes only and the patient may be unaware of the same. To pick up this abnormality, we need to monitor his heart rhythm for a long duration.

The patient who has a transient slow rhythm or fast rhythm may present with a history of the blackout. They have syncope. They fall with brief warning symptoms before the actual fall. This fall can cause injury and can be life-threatening also due to a vehicle accident. The patient usually goes to neurologist suspecting a neuro disease. However, his fall is due to a cardiac issue. Holter helps in establishing the diagnosis.

Some patients do have hysteria like illness, seizures. They are on treatment for this suspected disorders for a long time. But when put on long term Holter monitoring, it shows ECG abnormality exactly at the time of this seizure-like activity. Heart rhythm abnormality causes brain blood perfusion issue and presents as a neurological disease.

Instructions while on Holter monitoring 
  • Wear loose clothes
  • Better to have chest shaved off
  • Wear a small carry pouch with a strap across the neck to carry the device in it.
  • Take a bath before starting the monitoring. Do not take bath, shower, swim while on monitoring.
  • Maintain the logbook/diary of events occurring on the day of Holter monitoring.
  • Contact the technician if any of the electrodes become loose or fall off.
  • In case of any symptoms, note the exact time in a diary and press the trigger button on the device.
  • Do not rest, continue your normal daily routine.
  • Do not disconnect the device on your own. On next day, your Cardiology technician will disconnect the Holter.
  • Avoid areas of high voltage while wearing the monitor.
  • Reviewing the whole events and reporting will take time and you need to make an appointment for getting the treatment modification based on the report.
  • You should ask your doctor if any change in medicines is required or not.

If your doctor does have a very high suspicion of rhythm disorder and 24-hour Holter is normal, Doctor may advice repeating the test for another 24 hours.