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Holter monitor (24h) – Indications, Procedure, Result

A Holter monitor is a machine that continuously records the heart’s rhythms. The monitor is worn for 24 to 48 hours during normal activity.

How the Test is Performed

Electrodes (small conducting patches) are stuck onto your chest. These are attached by wires to a small recording monitor. You carry the Holter monitor in a pocket or pouch worn around your neck or waist. The monitor runs on batteries.

While you wear the monitor, it records your heart’s electrical activity.

  • Keep a diary of what activities you do while wearing the monitor, and how you feel.
  • After 24 to 48 hours, you will return the monitor to your health care provider’s office.
  • The provider will look at the records and see if there have been any abnormal heart rhythms.

It is very important that you accurately record your symptoms and activities so the provider can match them with your Holter monitor findings.

Electrodes must be firmly attached to the chest so the machine gets an accurate recording of the heart’s activity.

While wearing the device, avoid:

  • Electric blankets
  • High-voltage areas
  • Magnets
  • Metal detectors

Continue your normal activities while wearing the monitor. You may be asked to exercise while being monitored if your symptoms have occurred in the past while you were exercising.

How to Prepare for the Test

You DO NOT need to prepare for the test.

Your provider will start the monitor. You’ll be told how to replace the electrodes if they fall off or get loose.

Tell your provider if you are allergic to any tape or other adhesives. Make sure you shower or bathe before you start the test. You will not be able to do so while you are wearing a Holter monitor.

How the Test will Feel

This is a painless test. However, some people may need to have their chest shaved so the electrodes can stick.

You must keep the monitor close to your body. This may make it hard for you to sleep.

Occasionally there may be an uncomfortable skin reaction to the sticky electrodes. You should call the provider’s office where it was placed to tell them about it.

Why the Test is Performed

Holter monitoring is used to determine how the heart responds to normal activity. The monitor may also be used:

  • After a heart attack
  • To diagnose heart rhythm problems that may be causing symptoms such as palpitations or syncope (passing out/ fainting )
  • When starting a new heart medicine

Heart rhythms which may be recorded include:

  • Atrial fibrillation or flutter
  • Multifocal atrial tachycardia
  • Paroxysmal supraventricular tachycardia
  • Slow heart rate (bradycardia)
  • Ventricular tachycardia

Normal Results

Normal variations in heart rate occur with activities. A normal result is no significant changes in heart rhythms or pattern.

What Abnormal Results Mean

Abnormal results may include various arrhythmias such as those listed above. Some changes may mean that the heart is not getting enough oxygen.

Risks

Other than the uncommon skin reaction, there are no risks associated with the test. However, you should be sure not to let the monitor get wet.

 

 

Frequently Asked Questions

Is this article a replacement for a doctor?

No. It is educational content only. Patients should consult a qualified clinician for diagnosis and treatment.

When should I seek urgent care?

Seek urgent care for severe symptoms, rapidly worsening condition, breathing difficulty, severe pain, neurological changes, or any emergency warning sign.

References

Add references, clinical guidelines, textbooks, journal articles, or trusted medical sources here. You can edit this area later with a custom field named _rx_references.

Written by Dr. Harun Ar Rashid, MD - Arthritis, Bones, Joints Pain, Trauma, and Internal Medicine Specialist

Dr. Md. Harun Ar Rashid, MPH, MD, PhD, is a highly respected medical specialist celebrated for his exceptional clinical expertise and unwavering commitment to patient care. With advanced qualifications including MPH, MD, and PhD, he integrates cutting-edge research with a compassionate approach to medicine, ensuring that every patient receives personalized and effective treatment. His extensive training and hands-on experience enable him to diagnose complex conditions accurately and develop innovative treatment strategies tailored to individual needs. In addition to his clinical practice, Dr. Harun Ar Rashid is dedicated to medical education and research, writing and inventory creative thinking, innovative idea, critical care managementing make in his community to outreach, often participating in initiatives that promote health awareness and advance medical knowledge. His career is a testament to the high standards represented by his credentials, and he continues to contribute significantly to his field, driving improvements in both patient outcomes and healthcare practices. Born and educated in Bangladesh, Dr. Rashid earned his BPT from the University of Dhaka before pursuing postgraduate training internationally. He completed his MD in Internal Medicine at King’s College London, where he developed a special interest in inflammatory arthritis and metabolic bone disease. He then undertook a PhD in Orthopedic Science at the University of Oxford, conducting pioneering research on cytokine signaling pathways in rheumatoid arthritis. Following his doctoral studies, Dr. Rashid returned to clinical work with a fellowship in interventional pain management at the Rx University School of Medicine, refining his skills in image-guided joint injections and minimally invasive pain-relief techniques.