Implantable loop recorder
It only records - it delivers no therapy and is almost never the emergency. The point of this entry is to stop it distracting you.
Also called: ILR, implantable loop recorder, loop recorder, implantable cardiac monitor, ICM, Reveal, LINQ, event recorder
What it is
An implantable loop recorder is a small device, the size of a large USB stick, placed under the skin over the heart to monitor the rhythm continuously - usually to investigate unexplained blackouts or palpitations. The UK guidance is blunt about what it does: it records and stores abnormal rhythms, can be triggered by the patient after a symptom, and They do not deliver any therapy
.
It is included in this tool for one reason: so that a leadless lump on a chest film, or a device on the problem list, is correctly dismissed as a monitor and does not derail the assessment. Loop recorders are used in both adults and children (children usually for unexplained syncope or palpitations); the ED message - it is only a monitor - is identical in both.
How to recognise it
- A small, flat, leadless lump just under the skin on the front of the left chest, sometimes barely palpable; occasionally sited in the axilla.
- On a chest film: a small rectangular device with no leads running anywhere - the feature that separates it from a pacemaker.
- A history of being investigated for blackouts, collapse or palpitations, and a patient who may carry a small handheld activator to tag a symptom.
What it gets confused with
A loop recorder has no leads and delivers no therapy; a pacemaker or ICD has leads into the heart and treats the rhythm. If the film shows leads, it is not a loop recorder. Magnets, pad placement and deactivation worries that apply to pacemakers and ICDs do not apply here.
What goes wrong
Being mistaken for a device that matters
The recorder is noticed on examination or imaging and attention turns to it, or someone worries about magnets, MRI or deactivation.
Red flag
There is nothing to deactivate - loop recorders (the guidance calls them implantable event recorders): As IERs deliver no therapy there is no requirement for or ability to deactivate them
. It is not causing the patient's problem. Return to assessing the patient.
It holds the diagnosis you need
A patient presents after a blackout, arrhythmia or arrest and has a loop recorder in place.
Red flag
This is the one time the recorder is useful to you: it may have captured the rhythm during the event. Have cardiology interrogate it - the stored trace can be the whole diagnosis.
The first ten minutes
- Recognise it as a monitor and set it aside - it is not the cause of the presentation.
- If the presentation is a blackout, arrhythmia or collapse, ask cardiology to interrogate it for a captured trace spanning the event.
- Manage the actual clinical problem exactly as you would in a patient with no device - no magnet, pad-placement or deactivation considerations apply.
Do not
Who owns it
Cardiology owns the recorder and can interrogate it to retrieve stored rhythms. There is nothing for the ED to do to the device itself except arrange that interrogation when the stored trace would help.
When the device is not the problem
A patient with a device gets pneumonia, sepsis, pulmonary oedema and myocardial infarction at the same rate as everybody else. The device is the most visible thing about them and it attracts the whole assessment.
- The NTSP says it out loud
- The project's own manual warns that
patients with tracheostomies can become unwell with all the problems that other patients get too. It is easy to become fixated with the tracheostomy.
The same sentence applies to every device in this tool. - Clear the device, then leave it
- Establish that the device is doing its job — the stoma is patent, the line draws back, the pump is running — and then assess the patient as you would anyone else.
- The anchoring runs both ways
- The opposite error is treating a device complication as a medical illness: a blocked gastrostomy read as vomiting, a baclofen pump failure read as sepsis.
- NTSP manual — Red flags · read in full
Who to call
The team and the criteria are national. The phone number is local, and this tool does not know it. Find it once, now, and write it on the department's own card — that is the part no website can do for you.
- Say the device name first
- Open with laryngectomy, LVAD, shunt — the single word changes who comes and what they bring. Do not bury it in the history.
- Say what you have already established
- Whether the device is patent, whether it has been removed or disturbed, and what you have already tried. The specialist is deciding whether to walk or run.
- Ask who owns it out of hours
- Device ownership and the on-call route often differ from the implanting specialty, and it is frequently a regional centre rather than your own hospital.
- The patient's own team is a resource, not an afterthought
- Named nurse specialists, home-care companies and device helplines answer questions nobody else can, and the patient usually has the number.
What the patient will be carrying
Patients often carry a device identification card and a handheld symptom activator. The card names the device and the investigating cardiologist, which helps arrange interrogation.
Scope of this page
This page exists to correctly dismiss the loop recorder and point you back at the patient, and to flag the one time it helps - interrogation after an event. It does not cover the indications for implantation or the interpretation of stored traces, which are cardiology's. The message applies equally to adults and children with a recorder.