The first study to assess the clinical impact of remote monitoring with the Reveal LINQ implantable loop recorder (Medtronic) has demonstrated the benefits of this feature in early diagnosis of asymptomatic but serious arrhythmias in a significant proportion of patients.
The independent study, recently published in Europace, found that, during about one year of follow-up, 17% of patients received therapeutic interventions prompted by remote monitoring with the MyCareLink system (Medtronic) following asymptomatic arrhythmic events 3.8 months before the next theoretical scheduled in-office data download.
First author of the study Massimiliano Maines (Santa Maria del Carmine Hospital, Rovereto, Italy) and colleagues comment that for patients with asymptomatic but potentially serious arrhythmias it is current practice to download and review implantable loop recorder data in-office on a periodical basis (at their institution every six months). However, they write “this practice has the potential to delay the diagnosis and might result in significant clinical consequences such as recurrent syncope or cardioembolic stroke.”
The 2015 Heart Rhythm Society consensus on remote monitoring of cardiac devices (Slotwiner D et al, HeartRhythm 2015;12:e69–100) recognised that remote monitoring of implantable loop recorders “may be useful to avoid losing data that may be overwritten and to facilitate early diagnosis of asymptomatic events; however, interventional strategies based on remote monitoring of implantable loop recorders have yet to be evaluated.”
Maines et al comment that to the best of their knowledge this is the first study evaluating the clinical impact of implantable loop recorder remote monitoring. At their institution, they enrolled 154 patients (100 males, 63±15 year old), from July 2014 to June 2016, who were implanted with the Reveal LINQ implantable loop recorder. Implantations took place in a procedure room under local anaesthesia.
Indications included atrial fibrillation burden (n=37, 24%), palpitations (n=15, 10%), recurrent syncope of presumed cardiac origin (n=52, 34%), evaluation of ventricular arrhythmias burden (n=26, 17%) and cryptogenic stroke suspected to be secondary to atrial fibrillation (n=24, 15%).
During a mean follow-up of over a year, a diagnosis was made in 99 (64%) patients and in 60 (39%) one or more than one therapeutic interventions were established following recording of arrhythmias. In 26 (17%) of these 60 patients, including four patients with cryptogenic stroke who received a diagnosis of asymptomatic atrial fibrillation, remote monitoring prompted therapeutic interventions such as anticoagulation therapy start (n=8) pacemaker implantation (n=10), modification of antiarrhythmic therapy (n=4) and electrophysiology study/catheter ablation (n=4). In these patients, Maines et al note, mean time from the event detection to the next theoretical scheduled in-office evaluation was 3.8 months.
The authors comment that this earlier diagnosis was facilitated by the remote monitoring capability of the Reveal LINQ device and by their organisational model involving a “remote monitoring team” consisting of a specifically trained specialist nurse who reviewed the transmissions on a daily basis and reported significant new events to the electrophysiologist on duty.