The value of QT interval in differentiating vasovagal syncope from epilepsy in children

BACKGROUND: Both vasovagal syncope (VVS) and epilepsy present with transient loss of consciousness and are often difficult to identify. Hence this study aimed to explore the value of QT interval in the differentiation of VVS and epilepsy in children. METHODS: One hundred thirteen children with unexplained transient loss of consciousness were selected. 56 children with VVS (VVS group), including 37 males and 19 females, the average age is 9.88 ± 2.55 years old. 57 children with epilepsy (epilepsy group), including 36 males and 21 females, the average age is 8.96 ± 2.67 years old. At the same time, the 60 healthy individuals (control group) were examined according to age and sex. The QT interval of 12-lead electrocardiogram in a basal state of three groups was measured and statistically analyzed by SPSS 24.0 software. RESULTS: Compared with the control group, (1) QTcmax, QTcmin and QTcd were significantly longer in VVS group (P < 0.05), QTmax and QTmin were significantly shorter in VVS group (P < 0.05), and there were no significant differences in QTd between the two groups (P > 0.05). (2) The QTmax and QTmin were significantly shorter in epilepsy group (P < 0.05), and there were no significant differences in QTd, QTcmax, QTcmin, QTcd between the two groups (P > 0.05). Compared with the epilepsy group, The QTcmax, QTcmin, QTcd were significantly longer in VVS group (P < 0.05), and there were no significant differences in QTd, QTmax, QTmin between the two groups (P > 0.05). When QTcmax > 479.84 ms, QTcmin > 398.90 ms and QTcd > 53.56 ms, the sensitivity and specificity of diagnosing VVS were 62.5% and 77.19%, 82.14% and 50.88%, 82.14% and 38.60% respectively. CONCLUSION: QTcmax, QTcmin and QTcd have certain value in differentiating VVS from epilepsy in children. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13052-022-01388-2.