Implantable Loop Recorder (ILR)
An implantable loop recorder (ILR) is a small, metal, battery-operated device which records the heart’s rate and rhythm to detect any abnormalities over a long period of time, so it is ideal for patients who suffer very infrequent symptoms, or where they black out so they cannot activate an event recorder (see ambulatory ECG monitoring). The ILR is inserted under the skin on the chest wall under local anaesthetic and is about the same size as a USB stick device. It has a battery life of around 18-36 months. The data is accessed remotely i.e. it does not need to be removed to get the information from it, and if a patient feels the onset of symptoms, they can manually activate the ILR and the timing can be stored along with the trace before, during, and after the onset of symptoms.
Risks Include :
- a large, palpable bruise (1%) which may occasionally need to be drained; and
- infection (1%). All patients are pre-treated with a single dose of antibiotics to minimise this risk.