[Efficacy of midodrine hydrochloride in the treatment of children with vasovagal syncope].
OBJECTIVE
To explore the efficacy of midodrine hydrochloride in the treatment of vasovagal syncope (VVS) in children.


METHODS
Forty-eight children with unexplained syncope and prodromata (21 males, 27 females, aged 6 -17 years, mean 11 years +/- 3 years) were randomly assigned into 3 groups. They were health education group, cresol group and midodrine hydrochloride group respectively. Cresol group was comprised of children given cresol as first-line therapy in addition to health education and midodrine hydrochloride group patients given midodrine hydrochloride on the basis of cresol group. Repeated head-up tilt testing (HUTT) and follow-ups of at least 6 months were conducted to evaluate the therapeutic efficacy, side effects of midodrine hydrochloride and hemodynamic changes in treating pediatric VVS.


RESULTS
(1) The HUTT-based effective rate of 3 group was 20.0% (2/10), 60.9% (14/23) and 80.0% (12/15) respectively. It was significantly higher in cases of midodrine hydrochloride group and cresol group than that of health education group (P < 0.05). However,there was no significant difference in the HUTT-based effective rate between cresol group and midodrine hydrochloride group (P > 0.05). (2) During the follow-up period, the recurrence rate of syncope was significantly lower in midodrine hydrochloride group than in other two groups (P < 0.05). However, there was no significant difference in the recurrence rate of syncope between health education and cresol groups (P > 0.05). (3) There was no statistic difference in supine hemodynamic indices (HR, SBP, DBP) between before and after treatment in 3 groups. After midodrine therapy, the effects of midodrine upon changes in systolic and diastolic pressures and heart rate, between upright beginning and supine positions, were statistically significant (P <0.05).


CONCLUSIONS
Health education and cresol are conventional therapies for pediatric VVS. The efficacy can be enhanced by supplementing midodrine hydrochloride. Such a regimen is effective and safe in treating pediatric VVS.
Liu
Xiao-Yan
XY
Department of Cardiovascular Pediatrics, Second Xiangya Hospital, Institute of Pediatrics, Central South University, Changsha 410011, China.
Wang
Cheng
C
Wu
Li-Jia
LJ
Hu
Chun-Yan
CY
Lin
Ping
P
Li
Ming-Xiang
MX
Cui
Xiao-Li
XL
Xie
Zhen-Wu
ZW
D000293:Adolescent; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008879:Midodrine / Q000627:therapeutic use*; D019462:Syncope, Vasovagal / Q000188:drug therapy*; D018667:Tilt-Table Test; D016896:Treatment Outcome
D008879:Midodrine