Aetiologic and clinical characteristics of syncope in Chinese children

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

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.

Clinical Efficacy of Empirical Therapy in Children with Vasovagal Syncope

(1) Background: This case-control study was designed to assess the efficacy of empiric treatment for vasovagal syncope in children; (2) Methods: We retrospectively enrolled 181 children with vasovagal syncope from the Department of Pediatrics of Peking University First Hospital. The participants were categorized into four groups, based on the empiric treatment received: conventional treatment, including health education and orthostatic training; conventional treatment plus oral rehydration salts; conventional treatment plus metoprolol; conventional treatment plus midodrine hydrochloride. Patients were followed up to evaluate the syncopal or presyncopal recurrence. Kaplan-Meier curves were drawn to explore the syncopal or presyncopal recurrence in children, and the differences were compared among the groups using a log-rank test; (3) Results: Among the 181 children with vasovagal syncope, 11 were lost to follow-up. The median time of follow-up was 20 (8, 42) months. The Kaplan-Meier survival curve showed no significant difference in syncopal or presyncopal recurrence in children treated with different empiric options according to a log-rank test (χ2 = 1.328, p = 0.723); (4) Conclusions: The efficacy of unselected empiric therapy of vasovagal syncope in children was limited, and the individualized therapies merit further studies.

Geçici Bilinç Kaybıyla Başvuran Çocuk Olguların Retrospektif Değerlendirilmesi

Amaç: Çalışmamızın amacı , geçici bilinç kaybı (GBK) yakınması ile başvuran çocuk olguların tanılarının aydınlatılması, anamnez, etiyoloji, özgeçmiş ve soygeçmiş, fizik muayene ve laboratuvar bulgularının, tedavilerinin retrospektif değerlendirilmesidir. Gereç ve Yöntemler: Çalışmaya Süleymen Demirel Üniversitesi Tıp Fakültesi Hastanesine GBK yakınmasıyla 1 Ağustos 2017-1 Şubat 2020 tarihleri arasında çocuk polikliniklerine başvuran hastalar dahil edildi, kaydedilen anamnezleri, fizik muayene bulguları detaylı olarak geriye dönük incelendi. Yapılan biyokimyasal laboratuvar incelemeleri, elektrokardiyografi (EKG), transtorasik ekokardiyografi (EKO), 24 saatlik ritm holter EKG, kraniyal manyetik rezonans (MR) görüntüleme, elektroensefalografi (EEG) retrospektif olarak tanıya ve tedaviye yönelik değerlendirildi. Bulgular: Hastaların 110’u (%68.8) kız, 50’si (%31.2) erkek idi. Hastaların ortalama yaşı 11.4 (±4.8) idi. Hastaların geçirdikleri ortalama GBK sayısı 1.6 (±1.2) idi. Çalışmamızdaki hastaların %33’ü tekrarlayan GBK atakları ile başvurmuştu. Çalışmamızda GBK tanısına yönelik yapılan ileri incelemelerde en sık neden vazovagal senkop (VVS) (51 hasta, %31.9), ikinci olarak epilepsi/FK/AFK (febril konvülzyon/afebril konvülzyon) (41 hasta, %25.6), üçüncü olarak psikojenik senkop (28 hasta, %17.5 ) olarak saptanmıştır. Diğer nedenler de sırasıyla durumsal, katılma nöbeti, OH (ortostatik hipotansiyon), migren/SVO (serebrovasküler olay), kardiyojenik, BPPV (benign paroksizmal pozisyonel vertigo) olarak bulunmuştur. Hastalara yapılan biyokimyasal tetkikler, EKG, EKO, 24 saatlik ritm holter EKG, EEG, kraniyal MR incelemeleri analiz edildi ve değerlendirildi. Sonuç: GBK yakınmasıyla başvuran her hastadan ayrıntılı anamnez alınmalı, tam sistemik muayene yapılmalı ve EKG çekilmelidir. Kan testleri, EEG, EKO, nörogörüntüleme, 24 saatlik ritm holter EKG değerlendirmeleri ön tanıya yönelik istenmelidir.

Screening Pediatric Patients in New-Onset Syncope (SPINS) Study

Objectives. The primary objective is to determine the frequency of history findings associated with cardiac syncope. Second, to determine the frequency of abnormal electrocardiograms (EKG) in patients presenting with typical vasovagal syncope. Methods. Retrospective chart review from January 2006 to April 2017 of children aged 5 to 18 years presenting to the emergency department with a chief complaint of syncope. Target population was all patients with first episode of syncope and a documented EKG. Excluded patients were those with head trauma, drug intoxication, current pregnancy, seizure, and any endocrine problem. Patients with cardiac causes of syncope were identified by an abnormal EKG or echocardiogram. Specific history findings (past cardiac history, chest pain, palpitations, syncope with exercise, absence of prodrome with syncope) were compared with those with and without cardiac etiology of syncope. The possibility of missing a patient with cardiac cause of syncope based on specific history findings was identified. Results. Of the total 4115 visits of patients with chief complaints of syncope, 2293 patients (55.7%) met the inclusion criteria. Nine patients (0.39%) were identified with cardiac etiology of syncope. The remaining were determined to be of vasovagal origin. All patients with cardiac etiology of syncope were found to have one positive specific history findings. A total of 1972 patients were identified with absence of specific history findings; no patient had a cardiac etiology of syncope. Conclusions. This study identifies screening questions to identify cardiac syncope. Implementing these standard questions could potentially decrease resource utilization and time for evaluation as well as guide follow-up.

Demographic and clinical features of pediatric patients with orthostatic intolerance and an abnormal head-up tilt table test; A retrospective descriptive study

BACKGROUND

Clinical presentation varies in children with Orthostatic Intolerance. This study aimed to evaluate the epidemiological and clinical characteristics of pediatric patients with orthostatic intolerance (OI) and positive head-up tilt test (HUTT).

METHODS

This study was a retrospective review of clinical data from outpatients over 18 months period.

RESULTS

We included 112 patients with abnormal HUTT results. Females were 78 (70%). Mean age of presentation was 15.6 years (sd: 3.3). Fifteen percent were overweight, and 14% were obese. A headache and syncope were the most frequent presenting symptoms (46% and 29% respectively). Review of systems identified more patients with headaches (84%), Syncope (61%), presyncope (87%) and abdominal pain (29%). Except for fatigue being more prevalent during a review of systems among patients with severe OI (69%) compared to those with moderate OI (46%, p = 0.02), there was no statistically significant difference in the clinical presentation between investigator-defined moderate and severe OI. Comorbidities identified in this cohort were Chiari malformations (9%), idiopathic intracranial hypertension (9%), electroencephalographic abnormalities (8%) and patent foramen ovale (43%).

CONCLUSIONS

Adolescents, mainly females had OI. Patients with OI and abnormal HUTT predominantly had a headache, syncope, and presyncope during the presentation. Eliciting review of systems and using tools such as clinical questionnaire identifies significant clinical presenting features and comorbidities.

2018 Chinese Pediatric Cardiology Society (CPCS) guideline for diagnosis and treatment of syncope in children and adolescents

Syncope belongs to the transient loss of consciousness (TLOC), characterized by a rapid onset, short duration, and spontaneous complete recovery. It is common in children and adolescents, accounting for 1% to 2% of emergency department visits.Recurrent syncope can seriously affect children's physical and mental health, learning ability and quality of life and sometimes cardiac syncope even poses a risk of sudden death. The present guideline for the diagnosis and treatment of syncope in children and adolescents was developed for guiding a better clinical management of pediatric syncope. Based on the globally recent development and the evidence-based data in China, 2018 Chinese Pediatric Cardiology Society (CPCS) guideline for diagnosis and treatment of syncope in children and adolescents was jointly prepared by the Pediatric Cardiology Society, Chinese Pediatric Society, Chinese Medical Association (CMA)/Committee on Pediatric Syncope, Pediatricians Branch, Chinese Medical Doctor Association (CMDA)/Committee on Pediatric Cardiology, Chinese College of Cardiovascular Physicians, Chinese Medical Doctor Association (CMDA)/Pediatric Cardiology Society, Beijing Pediatric Society, Beijing Medical Association (BMA). The present guideline includes the underlying diseases of syncope in children and adolescents, the diagnostic procedures, methodology and clinical significance of standing test and head-up tilt test, the clinical diagnosis vasovagal syncope, postural orthostatic tachycardia syndrome, orthostatic hypotension and orthostatic hypertension, and the treatment of syncope as well as follow-up.

Canadian Cardiovascular Society and Canadian Pediatric Cardiology Association Position Statement on the Approach to Syncope in the Pediatric Patient

Pediatric syncope is a common problem that peaks in adolescence, for which there are few data or evidence-based consensus on investigation and management. This document offers guidance for practical evaluation/management of pediatric patients (age < 19 years) with syncope encountered in the acute or primary care setting. The writing committee used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Most syncope is vasovagal, which is benign and does not require extensive investigation. This Position Statement presents recommendations to encourage an efficient and cost-effective disposition for the many patients with a benign cause of syncope, and highlights atypical or concerning clinical findings associated with other causes of transient loss of consciousness. The prodrome and the circumstances around which the event occurred are the most important aspects of the history. Syncope occurring midexertion suggests a cardiac etiology. A family history, which includes sudden death in the young or from unknown causes or causes that might be suspected to be other than natural can be a red flag. The electrocardiogram is the most frequently ordered test, but the yield is low and the test is not cost-effective when applied broadly to a population of patients with syncope. We recommend an electrocardiogram when the history is not suggestive of vasovagal syncope and there are features suggestive of a cardiac cause like absence of a prodrome, midexertional event, family history of early-life sudden death or heart disease, abnormal physical examination, or new medication with potential cardiotoxicity. For most patients with syncope, medical testing is not required and lifestyle modifications without medications suffice to prevent recurrences.

Tilt angles and positive response of head-up tilt test in children with orthostatic intolerance

This study aimed at examining three tilt angle-based positive responses and the time to positive response in a head-up tilt test for children with orthostatic intolerance, and the psychological fear experienced at the three angles during head-up tilt test. A total of 174 children, including 76 boys and 98 girls, aged from 4 to 18 years old (mean 11.3±2.8 years old), with unexplained syncope, were randomly divided into three groups, to undergo head-up tilt test at the angles of 60°, 70° and 80°, respectively. The diagnostic rates and times were analysed, and Wong-Baker face pain rating scale was used to access the children's psychological fear. There were no significant differences in diagnostic rates of postural orthostatic tachycardia syndrome and vasovagal syncope at different tilt angles during the head-up tilt test (p>0.05). There was a significant difference, however, in the psychological fear at different tilt angles utilising the Kruskal-Wallis test (χ2=36.398, p<0.01). It was mildest at tilt angle 60° utilising the Kolmogorov-Smirnov test (p<0.01). A positive rank correlation was found between the psychological fear and the degree of tilt angle (r(s)=0.445, p<0.01). Positive response appearance time was 15.1±14.0 minutes at 60° for vasovagal syncope children. There was no significant difference in the time to positive response, at different tilt angles during the head-up tilt test for vasovagal syncope or for postural orthostatic tachycardia syndrome. Hence, it is suggested that a tilt angle of 60° and head-up tilt test time of 45 minutes should be suitable for children with vasovagal syncope.

Syncope in children and adolescents living in north-eastern Poland - scope of causes

PURPOSE

To investigate the diagnostic yield of different tests and asses the scope of causes in children referring to the hospital with a syncope in north-eastern Poland.

METHODS

A review of 386 consecutive patients (age 2-18 years) living in north-eastern Poland presenting to the cardiology department with a new onset syncope (which appeared to be neurally mediated by history) was undertaken. The patients underwent physical examination, laboratory tests, electrocardiography, 24-holter monitoring, head-up tilt-test, exercise test, echocardiography and electroencephalography. All the tests were performed in most of the patients, without ending the diagnostics after finding the first probable cause of loss of consciousness.

RESULTS

229 potential causes of syncope were found in 191 patients (49.4%), with 2 possible causes in 32 patients and 3 potential causes in 3 patients. The top 3 tests with the highest diagnostic yield were: head-up tilt test (41.4%), 24-holter monitoring (14.5%) and echocardiography (8.4%). Electroencephalography was useful in 3 patients (1.5%) and exercise test did not help in any patient.

CONCLUSION

In some children more than one potential cause of syncope was diagnosed. That might confirm multiple factors' causality of syncope. Head-up tilt-test has the highest diagnostic yield in children with syncope. If the diagnostic protocol is not very strict, one might find some crucial conditions in about 8.3% of patients.

Modified Calgary score in differential diagnosis between cardiac syncope and postural orthostatic tachycardia syndrome-associated syncope in children

The present study was designed to analyse the usefulness of a modified Calgary score system during differential diagnosis between cardiac syncope and postural orthostatic tachycardia syndrome-associated syncope through a large sample sized clinical investigation. The study included 213 children, including 101 boys and 112 girls, with cardiac syncope or postural orthostatic tachycardia syndrome-associated syncope in the age group of 2-19 years (mean 11.8 ± 2.9 years). A modified Calgary score was created, which was analysed to predict differential diagnoses between cardiac syncope and postural orthostatic tachycardia syndrome-associated syncope using a receiver operating characteristic curve. The median of modified Calgary scores for cardiac syncope was -5.0, which significantly differed from that of postural orthostatic tachycardia syndrome (0.0; p < 0.01). The sensitivity and specificity of a differentiation score of less than -2.5 was 96.3% and 72.7%, respectively. Owing to the fact that the modified Calgary score was an integer, when less than -3.0 the diagnosis could be considered as cardiac syncope. The modified Calgary score could be used to make an initial differential diagnosis between cardiac syncope and postural orthostatic tachycardia syndrome-associated syncope in the clinic.

The diagnostic protocol in children and adolescents with syncope: a multi-centre prospective study

AIM

The appropriate diagnostic protocol for children with syncope has not been well established. A diagnostic protocol was developed and prospectively implemented to improve the diagnostic performance of paediatricians.

METHODS

The study population included 474 consecutive patients (range 6-17 years) presenting with a syncopal spell in one of the five participating hospitals of China. In step 1, all patients underwent initial evaluation for history, physical examination, standing test and standard electrocardiography (ECG). In step 2, priority was given to cardiographic tests for possibly cardiogenic syncope, or electroencephalographic examination and brain imaging for suspected neurological syncope, or psychiatric tests for suspected psychiatric syncope. Patients with unexplained syncope underwent head-up tilt testing (HUT).

RESULTS

The initial evaluation gave a definite diagnosis in 59 (12.4%) and possible diagnosis in 54 of the 474 patients. Further testing gave a definite diagnosis for 326 patients (69.7%). After the entire diagnostic protocol, definite diagnosis was established in 385 patients (81.1%). Autonomic-mediated reflex syncope (AMS) accounted for 73.0% of cases. The average cost of diagnostic results per patient was RMB 1030.24 +/- 150.09 ($118.42 +/- 17.25).

CONCLUSION

The use of a simplified diagnostic protocol for children and adolescents with syncope improves diagnostic yield.