Ambulatory Electrocardiography Modalities in Pediatric Arrhythmia Detection and Management

Importance The diagnostic efficacy of different ambulatory electrocardiographic monitoring modalities in this patient population remains unclear. Objective To compare the diagnostic yield and clinical utility of 3 ambulatory electrocardiographic modalities in pediatric patients. Design, Setting, and Participants This single-center study took place at an outpatient clinic and an inpatient ward of National Taiwan University Children’s Hospital. Patients younger than 18 years who underwent ambulatory electrocardiographic monitoring between December 2022 and January 2025 were included. These data were analyzed February 2025 to March 2026. Exposure A continuous 7-day Holter device that functioned as an event recorder was used. Recordings from the first 24 hours were defined as the 24-hour Holter results. Main Outcomes and Measures Arrhythmias were categorized as major (tachyarrhythmia or bradyarrhythmia) or minor (extrasystolic arrhythmia). All patients were followed up for 1 year; the final arrhythmia diagnosis was used as the reference standard. The primary and secondary outcomes were detection of arrhythmia and a change in clinical management attributable to monitoring findings, respectively. Results In total, 435 children (235 female [54%] and 200 male [46%]; mean [SD] age, 12.3 [3.9] years) were included. The mean (SD) duration of analyzable ambulatory electrocardiographic data was 4.9 (1.7) days. Of 411 children who activated the event recorder, 10.7% had symptom-correlated arrhythmias. The 7-day Holter monitoring demonstrated a significantly higher rate of major arrhythmias (6.2%) than the 24-hour Holter or 7-day event recordings (2.3%; rate difference 95% CI, 1.9%-6.0%; P < .001). Seven-day Holter monitoring showed superior sensitivity (7-day Holter monitoring: 73%; rate difference 95% CI, 54.1%-84.6%; 24-hour Holter monitoring: 27%; rate difference 95% CI, 13.4%-43.1%; and 7-day event recorder: 27%, rate difference 95% CI, 13.4%-43.1%; P < .001) and a high negative predictive value (97.5%, 95% CI, 95.2%-98.6%). Tachyarrhythmias were associated with higher rates of management changes; management changed in 7.1% of patients with 7-day Holter monitoring, 1.6% with 24-hour Holter (rate difference 95% CI, 3.0%-7.6%; P < .001) and 2.8% with a 7-day event recorder (rate difference 95% CI, 2.0%-6.2%; P < .001). Conclusions and Relevance In this study of pediatric patients without structural heart disease who underwent electrocardiographic monitoring, 7-day continuous ambulatory electrocardiographic monitoring was associated with a significantly higher diagnostic yield than 24-hour Holter and 7-day event recording. Continuous monitoring may be preferred to detect tachyarrhythmias likely to influence clinical management.