Implantable loop recorders in the diagnosis and management of cardiac symptoms in children and adolescents

Implantable loop recorders (ILR) have emerged as long-term effective monitoring tools for severe or recurrent rhythm abnormalities or unexplained cardiac symptoms. Scarce information is available on the use and results of this technology in the pediatric age. Report of the results of a cohort of pediatric patients that benefited from ILR implantation. Retrospective chart review of clinical data, implantation indications, diagnostic recordings and changes in patient management in pediatric patients who underwent Reveal LINQ ILR implantation from January 2016 to February 2022 at a single pediatric cardiology department in a tertiary care children’s hospital. In a pediatric cohort of 155 patients (mean age at implantation 10.3 years), 98 patients (63%) had ILR transmissions, 41 (42%) of which demonstrated a diagnostic arrhythmia recording. The median time to a diagnostic transmission was 175 days. The most common abnormality was sinus pauses (37%), followed by ventricular tachycardia (30%). Of the total transmissions, 78 (80%) were patient-activated and 21% of them had pathological traces. From the device-activated transmission (n=33, 34%), 79% showed pathological tracings. Some of the transmissions were simultaneously patient and device-activated. In 80% of patients with an ILR-related diagnosis, there was an arrhythmia management plan change including medication change, a pacemaker or an implantable cardioverter defibrillator implantation, and an indication to perform an electrophysiology study. No major complications occurred; 4 patients (2.4%) had minor complications. ILRs have emerged as a new technology proven to be effective and safe in diagnosing and managing pediatric arrhythmias.