Abstract: AbstractObjectiveTo determine whether midodrine hydrochloride therapy could prevent vasovagal syncope (VVS) in pediatric patients. MethodsFortysix children with recurrent syncope were included in the study.They were assigned into 3 groups.Midodrine group consisted of children who were administered with midodrine hydrochloride as the firstline therapy in addition to the conventional therapy.Metoprolol group consisted of patients who were administered with metoprolol as the firstline therapy based on the conventional therapy.Conventional therapy group included patients who were only given conventional therapy.Repeated headup tilt test (HUT) and a followup at least for 6 months were conducted. ResultsThe HUTbased effective rate was 7500% for children treated with midodrine,6500% for children with metoprolol,and 2000% for children with conventional therapy.It was significantly higher in cases of midodrine group and metoprolol group than that of conventional therapy group.However,there was no significant difference in the HUTbased effective rate between patients in midodrine group and metoprolol group (P>005).During the followup period,the recurrence rate of syncope for children in midodrine group and metoprolol group was significantly lower than that of conventional therapy group (P<005,respectively).However,there was no significant difference in the recurrence rate of syncope between children in midodrine group and metoprolol group (P>005). ConclusionMidodrine is as effective as metoprolol in the treatment of VVS in children.Few side effects were observed in the present experiment.

Key words: Vasovagal, Children , Syncope

摘要： 目的探讨米多君对血管迷走性晕厥儿童的治疗效果。 方法将200307—200412在北京大学第一医院儿科就诊的46例晕厥反复发作、直立倾斜试验(HUT)阳性的血管迷走性晕厥患儿，分为米多君组、美托洛尔组及基础治疗组。首先应用HUT评价患儿的治疗反应及调整药物，所有患儿随访6个月后，如没有晕厥的发作者则停药，并继续随访。进一步评价患儿晕厥复发情况及药物的不良反应。 结果米多君组、美托洛尔组及基础治疗组3组患儿HUT转阴率分别为750%、650%及200%。米多君组及美托洛尔组患儿的HUT转阴率明显高于基础治疗组(P均<005)，而给药治疗的两组患儿的HUT转阴率差异无显著性(P>005)。在随访过程中，米多君组及美托洛尔组晕厥复发率分别为222%及307%，而基础治疗组的晕厥复发率为800%，前两组晕厥复发率显著低于后组(P均<005)。前两组之间的复发率差异无显著性(P>005)。 结论米多君可有效治疗血管迷走性晕厥儿童。

关键词: 米多君, 晕厥, 血管迷走性, 儿童