What is Holter Monitoring?

A Holter is a small device that continually records your heart rhythm for a period of usually 24 hours. It may assist your doctor to detect abnormalities that may not be felt by the patient or abnormal heart rhythms that can correlate to patient symptoms. It is also more likely to detect abnormal rhythms when compared to an ECG.

How to prepare for the test

It is important to wear loose fitting clothes.
Remove necklaces from around the neck and keep them off during the test.
Have a shower or bath before the test as you will not be able to shower/bath or swim during the time you are wearing the monitor.
Do not use oils/cream or talc on the chest area before having the monitor on.

How the test is performed

The chest area is mildly exfoliated and cleansed with an alcohol wipe.
Men may need chest hair shaved where the electrode stickers are to be placed.
Wires are then connected to the electrode stickers and tape is placed over the electrode wires to help secure them in place and prevent accidental detachment.

The monitor is placed in a small pouch which is then worn around the neck.
A diary is provided so the patient can record activity and symptoms, (ie walking the dog 5pm, palpitations 10am, feeling distressed 2pm etc).

There is also an EVENT button on the monitor which the patient presses for each activity or symptom causing an increase or change in heart activity. This diary will assist the doctor to understand each event at the time the EVENT button was pushed.
Use only a roll on deodorant during the test as sprays will over time damage the monitors. While we encourage normal daily activities, it is important to remember that heavy perspiration or very strenuous activity will cause a poor trace or may even detach the electrode stickers from the skin. If this happens, especially during the night, it is more than likely the test will need to be repeated.

What are the risks?

Holter monitoring is extremely safe. It is like carrying around a small musical device.
Some patients may be allergic to the adhesive on the electrodes or tape. If you have a known allergy to these, please advise the nurse or technician. In most cases the allergy is only minor and will not prevent the test from being performed.
Sometimes the tape and electrodes can cause redness or small blisters due to friction. If any skin irritation is apparent once the tape or electrode stickers are removed, please do not rub the skin or apply any creams or lotions to the sensitive area until the redness/irritation has disappeared.


  • Wear loose comfortable clothing.
  • Do NOT have a shower, bath or swim during the test.
  • Remove all necklaces during the test.
  • Use only roll on deodorant during the test.
  • Keep a diary during the test for symptoms or activity.
  • Press the EVENT button to note a change of heart rhythm or symptom occurring.
  • Bring a list of current medications and dosage.
  • Be mindful that strenuous physical activity may impact on the clarity of data recorded as well as impact on the adhesive quality of the electrode stickers due to perspiration on the skin.
  • Do NOT use lotions or rub the skin after the test if there is any redness or irritation.

What happens when the test is finished?

You will return to the doctor’s surgery or pathology laboratory where the monitor was originally put on.
If your GP requested the test with no further cardiac evaluation required by the Specialist at that time, the report will be forwarded back to them. Allow up to one week for the results to be forwarded to your doctor. If there is a more urgent problem that needs attention, the Cardiologist reporting on your test will contact your GP and discuss the findings and recommendations. You will then be contacted by your GP.

If the test was requested by your Cardiologist, a follow up appointment will be given to you to discuss the test results. Again, if results indicate that you need to be seen sooner than your follow – up appointment, you will be contacted directly.