Clinical Features Of Syncope In Children And The Value Of Electrocardiogram And Dynamic Electrocardiogram In The Diagnosis

Objective:To explore the etiology,clinical features of syncope in children and the value of electrocardiogram(ECG) and dynamic electrocardiogram(DCG)in the diagnosis.Methods:A total of 172 children with syncope were collected from the outpatient or inpatient department of Children’s Hospital of Chongqing Medical University from January 2012 to December 2015,and the etiology,clinical features, the results of ECG and DCG were sorted and analyzed retrospectively.Results:1. In a total of 172 patients,110 cases( 64.0%) were neurally mediated syncope(NMS), which included 50 cases(29.1%)of vasovagal syncope, 57 cases(33.1%)of postural tachycardia syndrome,and 3 cases(1.7%)orthostatic hypertension.Besides,36 cases(20.9%)were cardiac syncope(CS) and 26 cases(15.1%)were unexplained syncope.2. 36 patients with CS contained 22 cases with arrhythmias of which had bradyarrhythmia in 18 and tachyarrhythmia in 4, 7 cases of structural heart disease, 6 cases of structural heart disease with bradyarrhythmias and 1 cases of structural heart disease with bradyarrhythmias.21 cases had third degree atrioventricular conduction block.3.NMS was more common in school age and adolescent girls,syncope spells at standing position were found in 82.7% without lying position, pre-syncopes like persistent standing and position change in 93.6%, predromes like dizziness and blurred vision in 97.3% without convulsion and incontinence.4. CS can happen at any age and also in infants, syncope spells at various position were found with lying position, related with exertion mostly, absent of prodromes such as palpitations, accompanied with convulsion and incontinence and to have a history of heart disease partly.5. NMS patients had no abnormal ECG and a few abnormal dynamic electrocardiograms(DCG) and echocardiography(ECHO) but had nothing to do with the onset of syncope. 35 cases of CS patients completed the ECG with abnormalities in 94.3%, and 62.9% could diagnose directly. 36 cases of CS patients completed the ECHO with abnormalities in 75% and 19.4% can diagnose directly. 27 cases of CS patients completed the DCG with abnormalities in 94.3%, and 62.9%could diagose directly which including 3 cases that were abnormal ECG but couldn’t diagnose.Conclusions:Both NMS and CS had overt clinical features.CS had the high risk.The diagnosis of syncope in children should determine or exclude CS firstly. ECG was as a routine examination of syncope, DCG should not be a screening method for the diagnosis of the cause of syncope.Once suspected cardiac syncope, ECG and DCG should be done.