Introduction

A cardiac Holter monitor is a small, portable, non-invasive ambulatory device, used to record continuously the heart’s electrical activity in a 24–72 hour period. A cardiac Holter monitor is sometimes referred to as an ‘Ambulatory electrocardiography’ or ‘Ambulatory ECG’.

Cardiac Holter Monitors can provide the following information:

• Correlate any symptoms (chest pain, palpitations or syncope) the patient experiences with the heart’s electrical activity at that time;
  
• Record arrhythmias that occur, providing diagnostic information about the type of arrhythmia, how long it lasts, and what might trigger it;
  
• Determine the effectiveness of anti-arrhythmic medications.
  

The benefit of ambulatory ECG lies in its ability to examine continuously a patient over an extended period of time, permitting patient ambulatory activity while examining electrocardiographic activity in changing environmental situations (both physical and psychological).

Aim

To provide guidance on the management and troubleshooting of Holter Monitors. This clinical guideline applies to children requiring a Holter monitor during inpatient admission, children being discharged home with a Holter monitor and/or children having a Holter monitor applied during an outpatient clinic.

Definition of Terms

• Arrhythmia: Irregular heart rhythm. Some common childhood arrhythmias include supraventricular tachycardia (SVT), Long QT, Atrioventricular Heart Block, bradycardia, ectopic beats.  
• Cardiac Holter Monitor: Referred to in this clinical guideline as ‘Holter monitor’, is a small ambulatory, portable ECG device. Components include 3 electrodes and a Record Box.
• ECHO: Echocardiogram is an ultrasound test of the heart, helping to evaluate heart structure and blood flow. 
  
• ECG: Electrocardiogram is a diagnostic tool that measures and records the electrical activity of the heart via electrodes placed on the skin.
  
• Event Card: Small booklet to highlight the time of Holter Monitor attachment and removal, and to record activities of the child while the Holter Monitor is attached.
  
• Record Box: The box records and stores continuous heart rhythm data transmitted by the electrodes. The Record Box will indicate it is working by displaying the time and a “recording” message on the screen.
  

Considerations for Holter Monitor

• A Holter Monitor will be attached to a child of any age, requires further cardiac testing as per Cardiology team. 
• Holter Monitor’s may be used in conjunction with other diagnostic tests, i.e. ECHO, 12-15 lead ECG, blood test and/or exercise stress test.
  
• The Cardiologist will determine the length of time the Holter Monitor should be left on.
  
• The Cardiology team will order the Holter Monitor on EMR. 
• A Cardiac Technician is responsible for attaching the Holter Monitor and this is done during working hours. Bedside nurses should not “acknowledge order” or “complete order” on EMR as the Technicians require an active order to complete the test. 
• If a Holter Monitor is required after hours (i.e. over the weekend), often the Cardiology Fellow will attach it to the patient. 
• Prior to attaching the electrodes, the skin must be clean, dry and hair free. The chest may be cleaned with normal saline/warm soapy water to remove any oily residue. Hair on the chest may need to be shaved, to ensure the electrodes stick well. Extra mefix ^tm tape may be secured over the electrodes to reinforce attachment.
• Holter Monitors may be attached within an inpatient or outpatient setting.
  

Management

• Once the Holter Monitor is attached to the patient it must stay on the patient for the prescribed time, 24-72hrs.
  
• For inpatients with a Holter Monitor, nurses are encouraged to document the time of attachment and the prescribed time to take off. This should be documented in the progress notes as well as handed over during shift changes. 
• The Record Box should be checked once a shift to ensure the time and “recording” message is visible on the box.
  
• Inpatients with Holter Monitors attached can still have bedside continuous cardiac monitoring at the same time if clinically indicated. Patients with a Holter Monitor may leave the ward (if clinically stable) and if approved by the medical team. 
• The child is allowed to go about normal activities of daily living; however they must avoid getting the Holter Monitor wet, therefore no showers or baths. It is also recommended to avoid the following: electric blankets and magnets. Signals from such devices may affect recording.
• Ensure the Record Box is in a carry pouch while the child is ambulating to ensure dots remain attached.
• Parents/Caregivers should be educated and encouraged to document activities in the “Event’s Card” (see Appendix 1)

Removal of Holter Monitor

• After the prescribed time, the Holter Monitor is removed from the child and, together with the Event’s record, returned to RCH Diagnostic Cardiology, Ground Floor, reception A3. There is no need to ‘turn off’ the monitor, or touch any buttons once removed from the patient.

Returning Holter Monitor from home: 

• Families are given a pre-stamped envelope with appropriate address to return Holter Monitor with Event’s Record to Diagnostic Cardiology.
• The pre-stamped envelope will also have a "Registered Post Prepaid Label" for tracking purposes by the cardiac technicians.

Returning Holter Monitor from inpatient ward: 

• Holter Monitor and Event’s Card should be sent, via carps, to RCH Diagnostic Cardiology, Ground Floor, reception A3. Do not put Holter Monitor in pneumatic tube.
  
• In most cases the Cardiac Technician’s will go to the ward and remove the Holter Monitor from the patient close to the prescribed time (if during working hours).
  
• The cardiologist will analyse the Holter Monitor and organize follow-up with the child and family accordingly.
• If a patient is discharged with a Holter Monitor, but has not been given a pre-stamped envelope, please ask the parents or carers of the child to return the monitor to Specialist Clinics A3 during business hours or to Koala Ward reception desk if after hours.

Troubleshooting

• Holter monitor electrodes fall off (see Appendix 2): It is important to reattach as soon as possible, and document the event in the Event’s Card. Secure electrodes with extra tape to prevent them falling off again.
  
• Record box is blank: Inform Cardiac Technician during working hours as it may need to be replaced. However, if it is noticed after hours keep the electrodes on, document issue on Event’s Card and hand over so Cardiac Technicians can be informed during hours.
• Cardiac Technicians can be contacted on RCH extension 53902; otherwise contacting Cardiac Technician outside RCH call switchboard 9345 5522 and ask for “Cardiac Technician”.
  

Special considerations

Some children may experience minor skin irritation from the glue on the electrodes. If severe irritation occurs remove the electrodes and inform the cardiac team. It is rare that anaphylaxis will result, but perform skin, respiratory, circulatory and disability assessment regularly to ensure child is stable. If anaphylaxis occurs employ anaphylaxis guidelines.

Links

Clinical Practice Guidelines: Anaphylaxis

Appendix 1 - Holter monitor event card

Appendix 2 - Placement of Holter Monitor Electrodes and “Recording” Box 

Image: Placement of Holter Monitor Electrodes. Photo courtesy of RCH staff. Date unknown. 

Image: Active Holter Monitor displaying “Recording”. Photo courtesy of RCH Cardiology Clinic staff. 10 October 2024. 

Please remember to read the disclaimer.

The development of this nursing guideline was coordinated by Emily Mohd Faizal, CNS Koala Ward and Annabelle Santos, CSN, Koala Ward, and approved by the Nursing Clinical Effectiveness Committee. Updated February 2025.