Arrhythmia detection using an implantable loop recorder after a negative electrophysiology study in Brugada syndrome: observations from a multicenter international registry

Background Risk stratification in Brugada syndrome (BrS) remains controversial. In this respect, the role of electrophysiology study (EPS) has been subject of debate. In some centers, it is common practice to use an implantable loop recorder (ILR) after a negative EPS to help risk stratification. However, the diagnostic value of this approach has never been specifically addressed. Objective To describe the baseline characteristics and the main findings of a diagnostic work-up strategy using an ILR after a negative EPS in BrS. Methods We conducted a retrospective international registry including patients with BrS and negative EPS (ie, non-inducible VT/VF) prior to ILR monitoring. Results 65 patients from 8 referral hospitals in the Netherlands, Spain and UK were included (mean age 39 ± 16 years, 72% males). The main indication for ILR monitoring was unexplained syncope/presyncope (66.1%). During a median follow-up of 39.0 months (Q1 25.0 – Q3 47.6), 18 patients (27.7%) experienced 21 arrhythmic events (AEs). None of the patients died during follow-up. Bradyarrhythmias were the most common finding (47.6%), followed by atrial tachyarrhythmias (38.1%). Only 3 patients presented ventricular arrhythmias. AEs were considered incidental in 12 patients (66.7%). In 11 patients (61.1%), AEs led to specific changes in treatment. Conclusion The use of ILR after a negative EPS in BrS was a safe strategy that reflected the high negative predictive value of EPS for ventricular arrhythmia in this syndrome. Additionally, it allowed the detection of AEs in a significant proportion of patients, with therapeutic implications in most of them.