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

Malignant vasovagal syncope in children

BACKGROUND

Malignant vasovagal syncope (VVS) is a unique form of cardioinhibitory VVS, characterized by prolonged asystole. To deepen the understanding of this distinct type of VVS in children, this article reviews advancements in the potential pathogenesis, diagnostic approaches, clinical significance, and treatment controversies of malignant VVS in pediatric patients.

DATA SOURCES

This article was developed by reviewing the literature and studies in databases including PubMed and Chinese Journal Full-text Database up to September 2024. Search terms included "malignant vasovagal syncope" AND "children" or "vasovagal syncope" AND "asystole" AND "children".

RESULTS

To date, studies focused on malignant VVS in children remain limited. Theoretically, children with malignant VVS are at risk of physical or mental impairment due to this cardiac asystole, though no definite conclusions have been reached. The mechanism underlying the significant cardiac inhibition in malignant VVS remains unclear, and the treatment strategy of malignant VVS is debatable.

CONCLUSIONS

The understanding of children with malignant VVS is insufficient. Further research is required to evaluate the clinical features and the pathogenesis of pediatric VVS with cardiac asystole and to establish effective management strategies for malignant VVS. Video Abstract.

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.

Efficacy of catheter ablation in ganglionated plexus for malignant vasovagal syncope children

AIM

Malignant vasovagal syncope in children seriously affects their physical and mental health. Our study aimed to explore the efficacy of catheter ablation in ganglionated plexus with malignant vasovagal syncope children.

CONCLUSION

Catheter ablation of ganglionated plexus was safe and effective in children with malignant vasovagal syncope and can be used as a treatment option for these children.

METHODS

A total of 20 children diagnosed with malignant vasovagal syncope were enrolled in Beijing Children's Hospital, affiliated with Capital Medical University. All underwent catheter ablation treatment of ganglionated plexus. Ganglionated plexuses of the left atrium were identified by high-frequency stimulation and/or anatomic landmarks being targeted by radiofrequency catheter ablation. The efficacy of the treatment was evaluated by comparing the remission rate of post-operative syncopal symptoms and the rate of negative head-up tilt results. Safety and adverse events were evaluated.

RESULTS

After follow-up for 2.5 (0.6-5) years, the syncope symptom scores were decreased significantly compared with before treatment [3 (2-4) versus 5 (3-8) scores, P < 0.01]. Eighty-five per cent (17/20) children no longer experienced syncope, whilst 80% (16/20) children showed negative head-up tilt test after treatment. No adverse effects such as cardiac arrhythmia occurred in the children.

Adult vasovagal syncope with abdominal pain diagnosed by head-up tilt combined with transcranial doppler: a preliminary study

BACKGROUND

Syncope is a common condition that increases the risk of injury and reduces the quality of life. Abdominal pain as a precursor to vasovagal syncope (VVS) in adults is rarely reported and is often misdiagnosed.​.

METHODS

We present three adult patients with VVS and presyncopal abdominal pain diagnosed by synchronous multimodal detection (transcranial Doppler [TCD] with head-up tilt [HUT]) and discuss the relevant literature.

RESULTS

Case 1: A 52-year-old man presented with recurrent decreased consciousness preceded by six months of abdominal pain. Physical examinations were unremarkable. Dynamic electrocardiography, echocardiography, head and neck computed tomography angiography, magnetic resonance imaging (MRI), and video electroencephalogram showed no abnormalities. Case 2: A 57-year-old woman presented with recurrent syncope for 30 + years, accompanied by abdominal pain. Physical examination, electroencephalography, and MRI showed no abnormalities. Echocardiography showed large right-to-left shunts. Case 3: A 30-year-old woman presented with recurrent syncope for 10 + years, with abdominal pain as a precursor. Physical examination, laboratory analysis, head computed tomography, electrocardiography, and echocardiography showed no abnormalities. Syncope secondary to abdominal pain was reproduced during HUT. Further, HUT revealed vasovagal syncope, and synchronous TCD showed decreased cerebral blood flow; the final diagnosis was VVS in all cases.

CONCLUSIONS

Abdominal pain may be a precursor of VVS in adults, and our findings enrich the clinical phenotypic spectrum of VVS. Prompt recognition of syncopal precursors is important to prevent incidents and assist in treatment decision-making. Abdominal pain in VVS may be a sign of sympathetic overdrive. Synchronous multimodal detection can help in diagnosing VVS and understanding hemodynamic mechanisms.

Clinical and Autonomic Profile, and Modified Calgary Score for Children and Adolescents with Presumed Vasovagal Syncope Submitted to the Tilt Test

BACKGROUND

In the pediatric population, syncope is mainly from vasovagal (VVS) origin. Its evaluation must be done by clinical methods, and the tilt test (TT) can contribute to the diagnosis.

OBJECTIVES

To analyze the clinical profile, Calgary and modified Calgary scores, response to TT and heart rate variability (HRV) of patients aged ≤ 18 years with presumed VVS. To compare the variables between patients with positive and negative responses to TT.

METHOD

Observational and prospective study, with 73 patients aged between 6 and 18 years, submitted to clinical evaluation and calculation of scores without previous knowledge of the TT. It was done at 70º under monitoring for HRV analysis. P-value < 0.05 was the statistical significance criterion.

RESULTS

Median age was 14.0 years; 52% of participants were female, 72 had Calgary ≥ -2 (mean 1.80), and 69 had modified Calgary ≥ -3 (mean 1.38). Prodromes were observed in 59 patients, recurrence in 50 and trauma in 19. The response to TT was positive in 54 participants (49 vasovagal, with 39 vasodepressor responses), with an increase in the low frequency (LF) component and a decrease in the high frequency (HF) component (p < 0,0001). In the supine position, LF was 33.6 in females and 47.4 in normalized units for males (p = 0.02). When applying the operating characteristic curve for positive TT, there was no statistical significance for HRV and scores.

CONCLUSION

Most children and adolescents with a presumed diagnosis of VVS presented a typical clinical scenario, with a Calgary score ≥ -2, and a predominant vasodepressor response to TT. Greater sympathetic activation was observed in the supine position in males. Calgary scores and sympathetic activation did not predict the response to TT.

Syncope and Unresponsiveness in an Adolescent With Comorbid Cardiac Disease: An Illustrative Case Report and Literature Review of Functional Neurologic Symptom Disorder

BACKGROUND

This case report with an associated literature review explores the challenges, opportunities, and current evidence in creating a thoughtful diagnostic and management plan for an adolescent with functional neurologic symptom disorder and comorbid cardiac disease.

METHODS

We performed a literature review utilizing PubMed to identify the current evidence base related to pediatric functional neurologic symptom disorder in the setting of comorbid cardiac disease. Ultimately, 25 manuscripts were identified for inclusion in this study.

RESULTS

We reported the recent epidemiology, screening, diagnostic, and treatment measures utilized in pediatric syncope with a focus on differentiating psychogenic causes from serious cardiac and benign etiologies. We further described how psychiatric and psychological factors influence assessment, management, and outcomes.

CONCLUSIONS

This study provides current, evidence-based suggestions for the assessment, diagnosis, and management of pediatric syncope, with an emphasis on recognizing psychogenic causes of syncope. It includes a description of a novel case of functional neurologic symptom disorder in a pediatric patient with structural cardiac disease. The study highlights how the absence of standardized guidelines, heterogeneity in care delivery, and lack of concurrent mental health management led to worse outcomes.

Predictive value of EGSYS score in the differential diagnosis of cardiac syncope and neurally mediated syncope in children

Background and objective

Syncope is a common emergency with diverse etiologies in children. Among these, cardiac syncope (CS) is associated with high mortality and is usually difficult to diagnose. However, there is still no validated clinical prediction model to distinguish CS from other forms of pediatric syncope. The Evaluation of Guidelines in Syncope Study (EGSYS) score was designed to identify CS in adults and has been validated in several studies. In this study, we aimed to assess the ability of the EGSYS score in predicting CS in children.

Methods

In this retrospective study, we calculated and analyzed the EGSYS scores of 332 children hospitalized for syncope between January 2009 and December 2021. Among them, 281 were diagnosed with neurally mediated syncope (NMS) through the head-up tilt test, and 51 were diagnosed with CS using electrocardiography (ECG), echocardiography (ECHO), coronary computed tomography angiography (CTA), myocardial enzymes and genetic screening. The receiver operating characteristic (ROC) curve and Hosmer-Lemeshow test were used to evaluate the predictive value of the EGSYS score system.

Results

The median scores of 51 children with CS and 281 children with NMS were 4 [interquartile range (IQR): 3-5] and −1 (IQR: -2-1), respectively. The area under the ROC curve (AUC) was 0.922 [95% confidence interval (CI): 0.892-0.952; P &lt; 0.001], indicating that the EGSYS score system has good discrimination. The best cutoff point was ≥3, with a sensitivity and specificity of 84.3% and 87.9%, respectively. The Hosmer-Lemeshow test demonstrated satisfactory calibration (χ²=1.468, P &gt; 0.05) of the score, indicating a good fit of the model.

Conclusion

The EGSYS score appeared to be sensitive for differentiating CS from NMS in children. It might be used as an additional diagnostic tool to aid pediatricians in accurately identifying children with CS in the clinical practice.

Pediatric syncope: pearls and pitfalls in history taking

Syncope is a heterogeneous syndrome with complex underlying mechanisms, hence, the spectrum of patients presenting with syncope is broad. The diagnosis of syncope begins with history taking, and an accurate diagnosis can be established through correct history taking and interpretation. Building and interpreting patient history are the main factors that cause a diagnostic yield gap between experts and nonexperts. The most frequent source of error is a clinician's misconception rather than an inaccurate account of patient symptoms. Clinicians can have several diagnostic pitfalls while evaluating patient history, which can be avoided by in-depth understanding of the link between syncope pathophysiology and clinical clues. Furthermore, clinicians need to understand the clinical features of diseases that require differentiation from syncope, such as seizures. The use of confusing terms is one of the barriers that prevents accurate diagnosis and communication between doctors and patients. In this review, we address the terms of syncope and its essential history-taking components in connection with the mechanism of syncope.

Neurally Mediated Syncope in Children and Adolescents: An Updated Narrative Review

Syncope presents a proportion of up to 25% among children and adolescents and accounts for 0.9% of emergency room visits. Its most frequent aetiology is neurally mediated syncope, which includes vasovagal syncope and orthostatic hypotension. Up to 70% of the paediatric population with reflex syncope is female. There are usually precipitating factors and prodromes. This mini-review will discuss the particularities of the clinical presentation, diagnosis, modified Calgary score, indications and accuracy of the head-up tilt test, classification, and pathophysiology in four sequential phases. Prognostic data and the non-pharmacological and pharmacological approaches will also be reviewed and differences regarding reflex syncope in adults will be discussed.

Electrocardiogram in Pediatric Syncope: Practice Variation Among Pediatric Emergency Physicians

OBJECTIVES

We intended to assess emergency department physician's practice pattern and their motivations for obtaining electrocardiograms (ECGs) in pediatric vasovagal syncope presentations. We also explored if borderline ECG findings alters emergency department physicians' management in this population.

METHODS

We conducted a cross-sectional survey of emergency physicians enrolled in the Pediatric Emergency Research Canada network. The survey questionnaire introduced 2 clinical vignettes presenting a typical vasovagal syncope and a presentation suggestive of a cardiac etiology. Outcome measures included frequency investigations, specialist consultation, and disposition stratified by type of syncope presentation. We also evaluated which specific ECG findings were likely to change physicians' management and explored factors influencing the decision to perform or not perform the ECG.

RESULTS

The analyzable response rate was 47% (105/225). In the low-risk scenario, 51% of respondents requested an ECG, and none consulted the cardiology service, given that all requested investigations are normal. Forty-five percent of physicians modified their management if an ECG was reported as anything but totally normal. In the high-risk scenario, all respondents requested either a 12-lead ECG or a high-lead ECG, and 94% consulted the cardiology service. Physicians also identified clear differences in the motivations behind their decision to perform an ECG in typical vasovagal syncope.

CONCLUSIONS

This study highlights the significant practice variation in the evaluation and management of typical vasovagal syncope among physicians, which is informed by complex interactions of patient, provider, and institutional factors and the perceived clinical significance of borderline ECG findings.

[Catecholaminergic polymorphic ventricular tachycardia in adolescents: a clinical, electrocardiographic and genetic diagnosis]

Catecholaminergic polymorphic ventricular tachycardia is one of the most lethal channelopathies, characterized by ventricular arrhythmias triggered by stress or physical activity. We present the case of an adolescent who consulted for recurrent syncope precipitated by exercise. In the diagnostic approach, catecholaminergic polymorphic ventricular tachycardia was reached, with a mutation in the cardiac ryanodine receptor gene, Heterozygous c.14311G> A (p.v4771I exon 100), antiarrhythmic drugs and implantable cardioverter-defibrillator were necessary with satisfactory evolution. Clinical suspicion, stress test and genetic tests are essential for a timely diagnosis and management of this pathology.

Midodrine treatment in children with recurrent vasovagal syncope

BACKGROUND

Vasovagal syncope is the most common cause of syncope in childhood and its treatment is not at a satisfactory level yet. We aimed to investigate patients who were diagnosed with vasovagal syncope, did not benefit from conventional treatment, received midodrine treatment, and to evaluate their response to midodrine treatment.

METHODS

Files of 24 patients who were diagnosed with recurrent vasovagal syncope, did not benefit from non-pharmacological treatments, and received midodrine treatment during June 2017-October 2019 were retrospectively analysed.

RESULTS

In total, 24 patients received a treatment dose of midodrine at 5 mg/day (2.5 mg BID) included in the study. The mean number of syncope was 5.75 ± 2.67 prior to treatment. Following treatment, the mean number of syncope was 0.42 ± 0.89. It was observed that syncope episodes did not recur in 17 patients, but it recurred in 4 out of 7 patients in the first 3 months of the treatment and did not recur in the following months. The episodes improved in two patients with an increase in the treatment dose, but the syncope episodes continued in only one patient.

CONCLUSION

It was concluded that midodrine treatment was effective and safe in adolescents with recurrent vasovagal syncope.

Choosing Wisely Neurology: Recommendations for the Canadian Neurological Society

BACKGROUND

Choosing Wisely Canada (CWC) is a national branch of a global campaign advocating for fewer unnecessary tests and for optimizing patient care. Professional societies representing physicians, pharmacists, and nurses participate by generating lists of recommendations meant to reduce patient harm and resource mismanagement in healthcare. The Canadian Neurological Society (CNS) plays an important role in advocating for quality patient care demonstrated by deriving specific recommendations. This process is described.

METHOD

The CNS Choosing Wisely task force adapted 10 recommendations for Canadian neurology practice. These were approved by the CNS board, and subsequently ranked by CNS members.

RESULTS

Ten recommendations were brought forward and ranked in a survey completed by CNS members. Survey ranking is presented. The top five recommendations were selected and optimized, resulting in seven key recommendations.

CONCLUSION

The recommendations set forth by the CNS will help with resource stewardship and patient safety in the delivery of neurological care by healthcare providers in Canada.

Pathophysiology and Individualized Management of Vasovagal Syncope and Postural Tachycardia Syndrome in Children and Adolescents: An Update

Vasovagal syncope (VVS) and postural tachycardia syndrome (POTS) are the main forms of orthostatic intolerance in pediatrics and both are underlying causes of neurally-mediated syncope. In recent years, increasing attention has been paid to the management of VVS and POTS in children and adolescents. A number of potential mechanisms are involved in their pathophysiology, but the leading cause of symptoms varies among patients. A few studies thus have focused on the individualized treatment of VVS or POTS based on selected hemodynamic parameters or biomarkers that can predict the therapeutic effect of certain therapies and improve their effectiveness. This review summarizes the latest developments in individualized treatment of VVS and POTS in children and indicates directions for further research in this field.

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.

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.

A Population-Based Study of Syncope in the Young

BACKGROUND

The prevalence, hospitalization patterns, and outcomes of pediatric and adolescent syncope have not been rigorously characterized.

METHODS

Patients < 20 years presenting to an emergency department (ED) with a primary diagnosis of syncope (International Classification of Diseases, 10th revision, code R55) between fiscal year (FY) 2006/2007 and FY 2013/2014 in the province of Alberta, Canada were grouped according to discharge status from the ED, ie, (1) admitted to hospital and (2) discharged without admission. Temporal trends and differences in baseline characteristics, medication use, and outcomes between admitted and discharged patients were examined.

RESULTS

The prevalence of syncope increased from 143/100,000 population in FY 2006/2007 to 166/100,000 population in FY 2013/2014 (P < 0.01). The majority of the 11,488 patients who presented to the ED with syncope were discharged home (n = 11,214 [98%]). Cardiac disease was present in 12.7% and thoracic conditions were present in 8% of the study population. A majority of patients (66.2% admitted and 56.4% discharged; P = 0.018) were taking a prescription drug in the year before presentation. By 30 days, 26.1% of admitted patients had a second ED presentation and 8.1% had a rehospitalization. Among discharged patients, the 30-day repeated ED presentation rate was 11.7% and the hospitalization rate was 1.1%. By 1 year, the rates of repeated ED visits increased to 64.1% and 47.5%, and rehospitalization rates increased to 21.4% and 6.8% among admitted and discharged patients, respectively.

CONCLUSIONS

Our data suggest that pediatric and adolescent syncope is increasing in prevalence and represents a growing public health problem. This population has a high burden of comorbidities that likely contribute to increased health care resource use and polypharmacy.

Predictors of abnormal electrocardiograms in the pediatric emergency department

Background

Electrocardiograms (ECGs) are ordered in the pediatric emergency room for a wide variety of chief complaints.

Objectives

Criteria are lacking as to when physicians should obtain ECGs. This study uses a large retrospective cohort of 880 pediatric emergency department (ED) patients to highlight objective criteria including significant medical history and specific vital sign abnormalities to guide clinicians as to which patients might have an abnormal ECG.

Methods

Retrospective review of Pediatric ED charts in all patients aged < 18 years who had ECG performed during ED stay. Pediatric ED physician interpretation of the ECG, clinical data on vital signs and past medical history was collected from the medical record for analysis.

Results

Of 880 ECGs performed in the ED, 17.4% were abnormal. When controlled for medical history and demographic differences, abnormal ECGs were associated with age-adjusted abnormal ED vital signs including increased heart rate (odds ratio [OR] 1.85, 95% confidence interval [CI] 1.1-3.09) and increased respiratory rate (OR 1.74, CI 1.42-2.62). In a logistic regression analysis, certain chief complaints and history components were less likely to have abnormal ECGs including complaints of chest pain (OR 0.38, CI 0.18-0.80) and known history of gastrointestinal or respiratory condition (i.e., asthma) (OR 0.48, CI 0.29-0.79).

Conclusions

In this cohort of patients, those with a chief complaint of chest pain or known respiratory conditions and normal age-adjusted vital signs in the ED have low likelihood of an abnormal ECG.

Neurological Complications of Cardiac Disease

This article focuses on the complex interactions between the cardiovascular and neurologic systems. Initially, we focus on neurological complications in children with congenital heart disease both secondary to the underlying cardiac disease and complications of interventions. We later discuss diagnosis and management of common syncope syndromes with emphasis on vasovagal syncope. We also review the diagnosis, classification, and management of children and adolescents with postural orthostatic tachycardia syndrome. Lastly, we discuss long QT syndrome and sudden unexpected death in epilepsy (SUDEP), reviewing advances in genetics and current knowledge of pathophysiology of these conditions. This article attempts to provide an overview of these disorders with focus on pathophysiology, advances in molecular genetics, and current medical interventions.