Guidelines for the diagnosis and treatment of neurally mediated syncope in children and adolescents (revised 2024)

Abstract

Background: Significant progress has been made in the diagnosis and treatment of pediatric syncope since the publication of the "2018 Chinese Pediatric Cardiology Society (CPCS) guideline for diagnosis and treatment of syncope in children and adolescents" ("2018 Edition Guidelines"). Therefore, we have revised and updated it to assist pediatricians in effectively managing children with syncope.

Data sources: According to the "2018 Edition Guidelines", the expert groups collected clinical evidence, evaluated preliminary recommendations, and then organized open-ended discussions to form the recommendations. This guideline was developed by reviewing the literature and studies in databases including PubMed, Cochrane, EMBASE, China Biomedical Database, and Chinese Journal Full-text Database up to April 2024. Search terms included "syncope", "children", "adolescents", "diagnosis", and "treatment."

Results: The guidelines were based on the latest global research progress and were evidence-based. The classification of syncope etiology, diagnostic procedures, postural tests, such as the active standing test, head-up tilt test, and active sitting test, clinical diagnosis, and individualized treatment for neurally mediated syncope in pediatric population were included.

Conclusions: The guidelines were updated based on the latest literature. The concepts of sitting tachycardia syndrome and sitting hypertension were introduced and the comorbidities of neurally mediated syncope were emphasized. Some biomarkers used for individualized treatment were underlined. Specific suggestions were put forward for non-pharmacological therapies as well as the follow-up process. The new guidelines will provide comprehensive guidance and reference for the diagnosis and treatment of neurally mediated syncope in children and adolescents.

Keywords: Adolescents; Children; Diagnosis; Neurally mediated syncope; Treatment.

Fig. 1

Diagnostic procedure for pediatric syncope. ECG electrocardiogram, SS situational syncope, POTS postural orthostatic tachycardia syndrome, OH orthostatic hypotension, OHT orthostatic hypertension, STS sitting tachycardia syndrome, SHT sitting hypertension, CHD congenital heart disease, HUTT head-up tilt test, VVS vasovagal syncope, VVS-VI vasovagal syncope vasoinhibitory type, VVS-CI vasovagal syncope cardioinhibitory type, VVS-M vasovagal syncope mixed type. ^aFor children with normal physical examination and normal routine ECG findings, ECG is generally not helpful in determining possible reasons. For children with possible structural heart defects after medical history, physical examination, and routine ECG. ECG is a screening tool to detect abnormal cardiac structures or functions; ^bHolter ECG is a common test to determine the cause of syncope. However, because syncope is unpredictable, regular monitoring for only 24 hours makes it difficult to confirm or thoroughly rule out the association between arrhythmia and syncope. When diagnosing the cause of syncope, comprehensive judgment should be made together with history-taking and other tests. The possible reasons include asymptomatic sinus bradycardia, atrioventricular block, and endless supraventricular or ventricular tachycardia. For children with recurrent syncope, Holter ECG and ILR are important for diagnosis and differential diagnosis. For children with syncope induced by sports and emotions, an exercise test should be performed to detect potential arrhythmias. During exercise trials, first aid is prepared as a precaution; ^cfor patients with suspected sick sinus syndrome, atrioventricular conduction abnormalities, and/or all ventricular and supraventricular arrhythmias, the diagnosis can be confirmed by cardiac electrophysiological examination when necessary; ^dfor patients with suspected pulmonary hypertension or coronary heart disease, although ECG cannot clarify the diagnosis, cardiac catheterization and angiocardiography may be considered; ^efor patients with suspected hereditary disease, such as ion channel diseases, cardiomyopathy, or genetic metabolic diseases, and for those with a family history of genetic heart disease or sudden death, the diagnosis may be confirmed by metabolic disorder screening and/or genetic tests