Background: Postural tachycardia syndrome and vasovagal syncope are common causes of orthostatic intolerance in children. The supplementation with water, or salt, or midodrine, or β-blocker was applied to children with postural tachycardia syndrome or vasovagal syncope. However, the efficacy of such medication varied and was not satisfied. This review aimed to summarise the current biomarkers in the treatment of the diseases. Data sources: Studies were collected from online electronic databases, including OVID Medline, PubMed, ISI Web of Science, and associated references. The main areas assessed in the included studies were clinical improvement, the cure rate, and the individualised treatment for postural tachycardia syndrome and vasovagal syncope in children. Results: Haemodynamic change during head-up tilt test, and detection of 24-hour urinary sodium excretion, flow-mediated vasodilation, erythrocytic H2S, and plasma pro-adrenomedullin as biological markers were the new ways that were inexpensive, non-invasive, and easy to test for finding those who would be suitable for a specific drug and treatment. Conclusion: With the help of biomarkers, the therapeutic efficacy was greatly increased for children with postural tachycardia syndrome and vasovagal syncope.

Introduction: We aimed to evaluate changes in the cerebral blood supply in children during vasovagal syncope and to clarify the diagnostic value of transcranial Doppler for vasovagal syncope. Materials and methods: Patients were divided into three groups. Group 1 consisted of 31 patients who were symptomatic and whose head-up tilt test was positive. Group 2 comprised 21 patients who were symptomatic but whose tilt test was negative. Group 3 included 22 healthy children. For the diagnosis of vasovagal syncope, the tilt test was applied. For the subjects of the patient and control groups, the tilt test was repeated. The flow rates of bilateral middle cerebral arteries were continuously and simultaneously recorded with temporal window transcranial Doppler. Results: There were no statistically significant differences between the three groups with respect to age and gender distribution (p>0.05). When the bed was at an upright position, the maximum blood flow rate of the right middle cerebral artery was lower in Group 1 than in Group 2, although the decrease was more significant in comparison to the healthy control group (p<0.05). The minimum blood flow rate of the right middle cerebral artery was lower in Group 1 than the Group 2, although the decrease was more significant in comparison with the healthy control group (p<0.05). The maximum blood flow rate of the left middle cerebral artery was significantly lower in Group 1 than in the control group (p<0.05). Conclusion: Minimum and maximum blood flow rates are significantly decreased in patients tilt test (+) patients with vasovagal syncope during orthostatic stress.

Objective: At present, the haemodynamic diagnosis of orthostatic intolerance is based mainly on the head-up tilt table test, which is sometimes risky for patients. Thus, it is important to find objective and safe methods to differentiate haemodynamic patterns of orthostatic intolerance cases. Methods: In all, 629 children with orthostatic intolerance, either vasovagal syncope or postural orthostatic tachycardia syndrome, were included in the multi-centre clinical study. We analysed the association between the clinical manifestation and haemodynamic patterns of the patients. Results: Syncope after motion with a prodrome of chest distress or palpitations and the concomitant symptom(s) after a syncopal attack, with debilitation, dizziness or headache, were the most important variables in predicting the diagnosis of vasovagal syncope. The overall diagnostic accuracy was 71.5%. Conclusion: Complaint of syncope after motion with prodromal chest distress or palpitation and the concomitant symptom after a syncopal attack, with subsequent debilitation, dizziness or headache, were the most important variables in the diagnosis of vasovagal syncope in children with orthostatic intolerance.

Syncope is a common cause of presentation to the emergency department in the older population, who are at increased risk of syncope resulting in serious injury in the form of fractures, adverse cardiac outcomes and death, lack of confidence and mental health issues. Older patients can present diagnostic challenges due to multiple co-morbidities, polypharmacy and the problem of amnesia associated with transient loss of consciousness. The underlying cause of their syncope can be established through a structured approach, and targeted patient selection can limit inappropriate investigations in syncope assessment units and ensure appropriate treatments are instituted. A previous review article in this journal, by Nath and Kenny in 2005, examined the evidence surrounding various aspects of syncope, including prevalence, cause, risks, investigations and treatment. This review updates the evidence and guidelines on the aetiology, investigation and treatments of syncope in the older person, with emphasis on recent advances.