卡托普利治疗小儿血管迷走性晕厥的疗效及其机制

Effects of oral captopril on pediatric vasovagal syncope and its mechanism

目的观察卡托普利治疗小儿血管迷走性晕厥（ＶＳ）的疗效并探讨其机制。方法３４例直立倾斜试验（ＨＵＴ）重复性良好的阳性ＶＳ患儿分别口服安慰剂（安慰剂组）及卡托普利（卡托普利组），１周后复查ＨＵＴ；并利用荧光法测量ＨＵＴ检查前后血中儿茶酚胺（ＣＡ）的浓度。结果安慰剂组１７例ＶＳ患儿仅６例ＨＵＴ检查转阴；卡托普利组１７例均转阴。安慰剂组随访１６±１０个月１１例中有８例ＶＳ复发，而卡托普利组随访１９±３个月无１例复发。ＣＡ测定发现ＶＳ发作前血浆ＣＡ浓度异常增高，安慰剂对血浆ＣＡ浓度无影响，卡托普利则可有效地抑制ＣＡ的分泌。结论卡托普利可能是防治小儿ＶＳ发作的一类有效药物，在其防治机制中抑制ＣＡ的分泌可能占有不可忽视的地位。

Objective To investigate the therapeutic effects of oral captopril on pediatric vasovagal syncope (VS) and its mechanism. Methods Thirtyfour children with unexplained syncope and positive response to headupright tilt table test (HUT) were reexamined with HUT one week after administering captopril or placebo. Highspeed ionexchange column chromatography was used to determine the plasma catecholamine (CA) concentrations. Results Response to HUT was negative in 6 of 17 cases after administration of placebo but in all after captopril treatment. During the 19±3 months of followup study, none of the children who took captopril recurred but did 8/11 cases who took placebo. During 16±10 months of followup study, the plasma CA concentration before administration of captopril or placebo was significantly elevated during HUT compared to that at supine position. Captopril significantly inhibited the CA release from the sympathetic nerve ending, but placebo did not. Conclusion Administering angiotensin converting enzyme inhibitor orally may be effective for VS in children. The decrease of plasma CA levels may be involved in its mechanisms.