Implantable Loop Recorder (ILR)

Your doctor has advised you have an Implantable Loop Recorder (ILR) fitted to monitor your heart rhythm and rate. This leaflet will help you understand what will happen before, during and after the procedure.

How does my heart work?

Your heart is a muscle that pumps blood around your body. It has its own electrical system to keep it working properly. Some people develop problems with their heart’s electrical system leading to symptoms such as palpitations, dizziness or collapse. 

For many people a diagnosis can be made using tests such as, electrocardiogram – ECG (heart tracing) or a monitor (a 24 or 72 hour continuous tape recording of your heart rate and rhythm).

These tests only record information for short periods of time.  An ILR can record and store information for up to 3 years.

What is an ILR?

An ILR is a small electronic device in a metal casing. It is smaller than a packet of chewing gum or a USB computer memory stick. The ILR is fitted under the skin of your chest wall below your collar bone. It will monitor your heart rate and rhythm and record any abnormalities (problems).

Are there any risks and possible complications?

The risk of complication is very low. You will be monitored for signs of any problems throughout the procedure.

The risks and possible complications include:

• infection – Despite all care taken during the procedure, sometimes an infection may still develop.  If needed, you will be given antibiotics.
• conscious light sedation – This can sometimes cause problems with your breathing, heart rate and blood pressure.
• pain – You may feel a small amount of pain during or after the procedure.
• bleeding – If there is any bleeding after the procedure you must tell your nurse or contact the Unit.
• bruising – You may notice a little bruising to the skin around where the ILR was fitted.  This should settle over the next 4 weeks.
• scar – There will be a small scar visible on your chest wall.
• migration – The loop recorder can sometimes move slightly from the original place it was fitted.

What should I do before my ILR is fitted?

You may wish to arrange for someone to take you home. Depending on the type of job you do you may need to arrange time off work.  Your doctor or nurse will discuss this with you.

You can expect to be at the Cardiology Day Unit for most of the day. There is limited space in the unit so only in special cases will anyone be allowed to stay with you, for example, patients with special needs.

Please bring with you a list of all the medications (drugs) you are currently taking, either prescribed by your doctor or those you have bought yourself, to your pre-assessment appointment and when you are admitted for your procedure.

Unless advised you should use your inhalers and take your tablets or medicines as usual.  The pre-assessment nurse will also tell you if you need to stop any medication (drugs) such as, anticoagulants (blood thinners) or antiplatelets (medications to stop your platelets from sticking together and causing clots)

Unless you are told otherwise you can eat and drink as usual before your procedure.

If possible please bring a dressing gown and slippers, and you may wish to bring something to read or music to listen to. Please bring your reading glasses (if needed) as you will need to read and sign a consent form.

Where will I go to have my ILR fitted?

Your procedure will be carried out in the Cardiology Day Unit at the University Hospital of North Tees.  You will be sent a letter telling you when and where to come.

It is important you arrive at your appointment time so we can prepare you for your procedure and answer any further questions you may have.  We are unable to give you an exact time for your procedure but we will keep you fully informed.

Who will be present during my procedure?

Your ILR will be implanted by a specialist nurse or a cardiologist. There will be a healthcare assistant present to help them and look after you.

You will be asked if you consent to have any observers or learners present during your procedure. Healthcare professionals in training may take part in your procedure according to their experience and stage of training. They will be supervised by fully qualified staff at all times.

North Tees and Hartlepool NHS Foundation Trust is a teaching organisation. We could not train future nurses, doctors and other health professionals without the co-operation of patients.

What will happen when I arrive at the Cardiology Day Unit?

A nurse will show you to a curtained bedspace or sideroom in the day unit. You will need to undress and put on a theatre gown. The information given at your pre-assessment appointment will be checked for changes.

Your blood pressure, pulse and temperature will be checked. A cannula (a fine tube) will be inserted into a vein in your arm or the back of your hand using a small needle. This allows blood samples to be taken and medication to be given.

A doctor or nurse will explain the procedure again and also confirm you have signed a consent form.

What will happen during the procedure?

The procedure takes about 30 minutes. You will be taken to the procedure room and asked to lie on a theatre bed. A nurse will stay with you to make sure you are comfortable.

You will be connected to equipment to monitor your heart rate and rhythm, blood pressure and blood oxygen levels.

Your upper chest will be cleaned with an antiseptic solution and sterile drapes placed over your upper chest leaving a small area where your ILR is to be fitted.

You will be given a local anaesthetic which means you will be awake during your procedure. A local anaesthetic drug will be injected into your skin around the site of your procedure to numb the area, so you will only be able to feel pressure but not pain. If needed, extra painkillers can be given; please tell your doctor or nurse if you feel any pain.

A small incision (cut) will be made below your collarbone and a small “pocket” (space) made under your skin for the ILR. When the ILR is in place the wound is closed using dissolvable sutures (stitches) and a sterile dressing is put over the wound.

What happens after the procedure?

After the procedure you will be taken back to your bed to rest for a few hours.  We will continue to monitor (check) your blood pressure, pulse, temperature and wound.  You will be offered drinks and something to eat.

A cardiac physiologist will see you to explain how to activate (use) the ILR device and answer any questions you may have. Before you go home your doctor or nurse will see you again and answer any questions you may have.

When can I drive?

You should not drive for 24 hours after the procedure. You may wish to place a small cushion or pad under your seatbelt over the area of your loop recorder for 1 to 2 weeks.

Will I need a follow-up appointment?

You will be given a follow-up clinic appointment to see a physiologist to allow your wound to be checked and information to be downloaded from the ILR to check it is working properly.  This will be about 5 weeks after your procedure.

What should I do if I have any symptoms?

The ILR automatically records your heart rhythm and rate but if you feel any symptoms such as dizziness or palpitations you should press your activator switch to tell the ILR to store your heart rhythm to memory. 

You should do this within 5 minutes of your symptoms starting, but only if it can be done safely. Once you recover, you should contact the physiologist as soon as possible so the information can be downloaded (See contact numbers).

The ILR has a limited memory so only activate it if you have symptoms.

Will my loop recorder be affected by household items?

No, you can use all electrical items including a mobile phone as usual.

Will security systems affect my loop recorder?

No, but you will need to tell airport security you have an ILR fitted.

What should I do if I need any hospital tests, treatment or a general anaesthetic?

In most cases this should not be a problem but it is important to tell your doctor or healthcare professional you have an ILR fitted. They will be able to get further information from the clinic.

Contact numbers

If you need further advice, or have any problems, please contact the appropriate number below.

University Hospital of North Tees

Loop Recorder Clinic

Cardiac Investigations Unit

telephone: 01642 624500

Monday to Friday, 9.00am to 5.00pm

Non-urgent messages can be left at any time on the answering machine.

Cardiology Day Unit

telephone: 01429 522020

Monday to Friday, 8.30am to 5.00pm

If no reply leave a message or telephone: 01429 522021

(These are Hartlepool codes but you will be diverted to North Tees.) 

University Hospital of Hartlepool

Loop Recorder Clinic

Cardiac Investigations Unit

telephone: 01429 522249

Monday to Friday, 9.00am to 5.00pm

Non-urgent messages can be left at any time on the answering machine.

Further information is available from:

NHS Choices

telephone: 111 (when it is less urgent than 999)

Calls to this number are free from landlines and mobile phones

Further information on the NHS Choices website

British Heart Foundation

Compton House,
2300 The Crescent,
Birmingham Business Park,
Birmingham,
B37 7YE

telephone: 020 7554 0000

Heart helpline: 0300 330 3311

Monday to Friday, 9.00am to 5.00pm

Further information on the British Heart Foundation website

Arrhythmia Alliance

P O Box 3697,
Stratford-upon-Avon,
Warwickshire,
CV37 8YL

telephone: 01789 450 787

24 hours a day, 7 days a week

Further information on the Arrhythmia Alliance website

Comments, concerns, compliments or complaints

Patient Experience Team (PET)

We are continually trying to improve the services we provide. We want to know what we’re doing well or if there’s anything which we can improve, that’s why the Patient Experience Team (PET) is here to help. Our Patient Experience Team is here to try to resolve your concerns as quickly as possible. The office is based on the ground floor at the University Hospital of North Tees if you wish to discuss concerns in person. If you would like to contact or request a copy of our PET leaflet, please contact:

Telephone: 01642 624719

Freephone: 0800 092 0084

Opening hours: Monday to Friday, 9:30am to 4pm

Email: [email protected]

Out of hours

Out of hours if you wish to speak to a senior member of Trust staff, please contact the hospital switchboard who will bleep the appropriate person.

Telephone: 01642 617617

Data protection and use of patient information

The Trust has developed Data Protection policies in accordance with Data Protection Legislation (UK General Data Protection Regulations and Data Protection Act 2018) and the Freedom of Information Act 2000. All of our staff respect these policies and confidentiality is adhered to at all times. If you require further information on how we process your information please see our Privacy Notices.

Telephone: 01642 383551

Email: [email protected]

Leaflet feedback

This leaflet has been produced in partnership with patients and carers. All patient leaflets are regularly reviewed, and any suggestions you have as to how it may be improved are extremely valuable. Please write to the Clinical Governance team, North Tees and Hartlepool NHS Foundation Trust, University Hospital of North Tees, TS19 8PE or:

Email: [email protected]