Single-centre use of implantable loop recorders in patients with congenital heart disease

Aims To determine the efficacy of the implantable loop recorder (ILR) in patients with congenital heart disease. Methods and results Retrospective data analyses of all patients with congenital heart disease undergoing ILR implantation in a congenital cardiac centre. Of 78 ILRs implanted between July 2000 and October 2007, 22 (15 male) patients had congenital heart disease. The median age at implantation was 15.5 years (7.0-46.5). Six patients had neurodevelopmental delay. Indications for implantation were syncope (n = 15), palpitations (n = 4), and pre-syncope (n = 3). Median implantation time was 19 months (1-30). Explantation data were available in 16 patients (73%). Implantable loop recorders were explanted following establishment of positive diagnosis (n = 3), negative diagnosis (n = 7), and at the end of battery life (n = 4). One patient died with the ILR in situ. One device eroded after 2 months without further complication. Following ILR interrogation, diagnosed arrhythmias included ventricular tachycardia (n = 2) and sinus node dysfunction (n = 1). On the basis of these findings, two patients had intracardiac defibrillators and one patient had a dual-chamber pacemaker implanted. Conclusion Implantable loop recorders lead to a positive or negative arrhythmic diagnosis following explantation in 71% of patients with congenital heart disease. This is particularly beneficial in patients with neurodevelopmental delay where accurate history is often limited.