Healthcare Utilization and Use of Implantable Cardiac Monitors in Syncope of Unknown Origin

BACKGROUND: Syncope of unknown origin ('SUO') is a challenge for clinicians. Investigation and admission rates vary despite attempts at standardization. Implantable cardiac monitors (ICMs) are valuable in streamlining work-up for SUO. OBJECTIVES: Compare admission rates in SUO in our ED to European Society of Cardiology ('ESC') 2018 guidelines and Canadian Syncope Risk Score ('CSRS') recommendations. Secondary outcomes included assessing clinician adherence to ESC and CSRS, differences between admission rates and syncope recurrence across age and gender, and healthcare utilization and outcomes over 24-months including ICM insertion when indicated. METHODS: Retrospective review of 50 patients with SUO in 2020. Admission rates were compared to the ESC and CSRS recommendations for significance. ICM was indicated for recurrent SUO > 30 days apart. RESULTS: Admission rates (64%) weren't significantly higher than ESC (60%) or CSRS (54%). Adherence was 83%-89% for admissions and 65% for discharges. Admitted patients were older with no difference in recurrence. Gender differences for admission rates or recurrence weren't significant. Admissions were diagnostic for 25%. Rates of most investigations were reduced compared to prior studies. 26% suffered recurrence and 10% injuries. ∼20% of patients met indications for ICM, and 89% meeting criteria received one. CONCLUSIONS: Our study shows no difference in admission rates in SUO compared to ESC or CSRS with 83%-89% adherence for admissions, and 65% for discharge, high diagnostic yield (25%) for admissions and reduced low-yield investigations with appropriate use of ICMs as an early investigation for recurrent SUO.