Different patterns of tilt-table test outcome in children and their response to medications

Abstract

Background Syncope is a common and often frustrating clinical problem encountered by pediatricians in outpatient or emergency room settings. Neurocardiogenic syncope is believed to be the most common cause of syncope in the absence of structural heart disease. In our study, we aimed to study different responses to tilting-table test among children and teenagers with suspected neurocardiogenic syncope. Patients and methods We collected data from patients of Ain Shams Hospital who presented with more than two attacks of syncope and got positive tilt-table test findings. All the patients were subjected to thorough history taking, full cardiac examination, and a tilt-table test. Patients were later followed up for 2 months for recurrence. Results Our study included data from 30 patients, of which 19 were females, and seven were on antiepileptic drugs. Approximately 20% of patients had a family history of epilepsy, and 10% had a family history of syncope. Prolonged standing especially in hot weather was the most common predisposing factor for their syncopal attacks. Palpitation and dizziness were the most common symptoms occurring before the attack, whereas palpitation and headache commonly affected these patients after syncope. Physical examination of these patients revealed no specific abnormality, and their hemoglobin level and random blood sugar level also revealed no specific abnormality. Tilt-table test was done to all the patients and revealed that ∼75% showed a vasodepressor response; however, only ∼23% showed a mixed response and no patients demonstrated cardioinhibitory response. No complications were reported during the test. The study revealed a significant negative correlation between the frequency of the attacks and initiation-response lag (r=−0.676, P<0.001), meaning that the more the attack numbers of syncope, the earlier the occurrence of positive response in tilt-table test. All patients in the study received midodrine tablets together with diet modification and tilt training for 2 months. They were followed up for recurrence of syncope and only ∼16% of these patients showed recurrence. On asking patients with recurrence, they stated that they were noncompliant neither to the treatment nor to the exercise. Conclusion It is evident that tilt-table test is a safe and effective test to diagnose neurocardiogenic syncope in children and teenagers and that vasodepressor response is more common than both mixed and cardioinhibitory responses in children and teenagers. Midodrine, diet modification, and tilt training are effective management of neurocardiogenic syncope in children and teenagers.