Pediatric Syncope: A Systematic Review

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.

Inequitable access: factors associated with incomplete referrals to paediatric cardiology

OBJECTIVE

To assess the variables associated with incomplete and unscheduled cardiology clinic visits among referred children with a focus on equity gaps.

STUDY DESIGN

We conducted a retrospective chart review for patients less than 18 years of age who were referred to cardiology clinics at a single quaternary referral centre from 2017 to 2019. We collected patient demographic data including race, an index of neighbourhood socio-economic deprivation linked to a patient's geocoded address, referral information, and cardiology clinic information. The primary outcome was an incomplete clinic visit. The secondary outcome was an unscheduled appointment. Independent associations were identified using multivariable logistic regression.

RESULTS

There were 10,610 new referrals; 6954 (66%) completed new cardiology clinic visits. Black race (OR 1.41; 95% CI 1.22-1.63), public insurance (OR 1.29; 95% CI 1.14-1.46), and a higher deprivation index (OR 1.32; 95% CI 1.08-1.61) were associated with higher odds of incomplete visit compared to the respective reference groups of White race, private insurance, and a lower deprivation index. The findings for unscheduled visit were similar. A shorter time elapsed from the initial referral to when the appointment was made was associated with lower odds of incomplete visit (OR 0.62; 95% CI 0.52-0.74).

CONCLUSION

Race, insurance type, neighbourhood deprivation, and time from referral date to appointment made were each associated with incomplete referrals to paediatric cardiology. Interventions directed to understand such associations and respond accordingly could help to equitably improve referral completion.

A framework to simplify paediatric syncope diagnosis

This paper aims to improve the diagnosis of syncope and transient loss of consciousness (TLOC) in children. Diagnostic problems stem, first, from some causes spanning various disciplines, e.g. cardiology, neurology and psychiatry, while the most common cause, vasovagal syncope, is not embraced by any specialty. Second, clinical variability is huge with overlapping signs and symptoms. Third, the approach to TLOC/syncope of the European Society of Cardiology (ESC) is underused in childcare. We explain the ESC guidelines using an additional paediatric literature review. Classification of TLOC and syncope is hierarchic and based on history taking. Loss of consciousness (LOC) is defined using three features: abnormal motor control including falling, reduced responsiveness and amnesia. Adding a < 5 min duration and spontaneous recovery defines TLOC. TLOC simplifies diagnosis by excluding long LOC (e.g. some trauma, intoxications and hypoglycaemia) and focussing on syncope, tonic-clonic seizures and functional TLOC. Syncope, i.e. TLOC due to cerebral hypoperfusion, is divided into reflex syncope (mostly vasovagal), orthostatic hypotension (mostly initial orthostatic hypotension in adolescents) and cardiac syncope (arrhythmias and structural cardiac disorders). The initial investigation comprises history taking, physical examination and ECG; the value of orthostatic blood pressure measurement is unproven in children but probably low. When this fails to yield a diagnosis, cardiac risk factors are assessed; important clues are supine syncope, syncope during exercise, early death in relatives and ECG abnormalities.  Conclusions: In adults, the application of the ESC guidelines reduced the number of absent diagnoses and costs; we hope this also holds for children. What is Known: • Syncope and its mimics are very common in childhood, as they are at other ages. • Syncope and its mimics provide considerable diagnostic challenges. What is New: • Application of the hierarchic framework of transient loss of consciousness (TLOC) simplifies diagnosis. • The framework stresses history-taking to diagnose common conditions while keeping an eye on cardiac danger signs.

Assessment of paediatric exertional or peri-exertional syncope: does the story matter?

Exertional syncope has been suggested to correlate with a cardiac aetiology, particularly when occurring in mid-stride. The aim of the study is to evaluate the incidence of cardiac disease among children presenting with exertional syncope, determine the influence of timing within activity, and determine the utility of genetic testing and implantable event monitors in the evaluation of cardiac syncope. The patients ≤18 years old with exertional syncope who underwent exercise stress testing between 2008 and 2019 were retrospectively included. Patients were assessed to be in one of three groups: mid-exertion (mid-stride syncope), peri-exertion (syncope during activity but not moving), and post-exertion (within minutes of the activity). A total of 334 patients were included; 46 % were mid-exertion, 18 % were peri-exertion, and 36 % were post-exertion. Thirteen patients (3.8 %) were diagnosed with cardiac syncope; n = 9 (69 %) mid-exertion. Only mid-exertional syncope was significantly associated with a cardiac diagnosis (OR: 2.6). Cardiac diagnoses included inherited arrhythmia syndromes (n = 9), abnormal coronary origins (n = 2), and supraventricular tachycardia (n = 2). Only catecholaminergic polymorphic ventricular tachycardia (n = 5) was associated with mid-exertional syncope (OR: 1.4). The definitive diagnostic test was exercise testing (n = 8), echocardiogram (n = 2), genetic testing (n = 1), ambulatory monitor (n = 1), and EKG (n = 1). Mid-stride syncope was more likely to result in a cardiac diagnosis, and exercise testing is the most common definitive test as catecholaminergic polymorphic ventricular tachycardia was the primary aetiology of exertional syncope in our cohort. Implantable event monitors and genetic testing could be helpful in ruling out cardiac disease.

Markers for predicting the efficacy of beta-blockers in vasovagal syncope management in children: A mini-review

Vasovagal syncope (VVS) is a common subtype of neurally mediated syncope. It is prevalent in children and adolescents, and critically affects the quality of life of patients. In recent years, the management of pediatric patients with VVS has received extensive attention, and β-blocker serves as an important choice of the drug therapy for children with VVS. However, the empirical use of β-blocker treatment has limited therapeutic efficacy in patients with VVS. Therefore, predicting the efficacy of β-blocker therapy based on biomarkers related to the pathophysiological mechanism is essential, and great progress has been made by applying these biomarkers in formulating individualized treatment plans for children with VVS. This review summarizes recent advances in predicting the effect of β-blockers in the management of VVS in children.

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.

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.

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.