Zhang Qingyou, Jin Hongfang, Wang Li, Chen Jianjun, Tang Chaoshu, Du Junbao
Department of Pediatrics, Peking University First Hospital, and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China.
Med Sci Monit. 2008 Apr;14(4):CR199-203.
Previous studies that have assessed the effects of beta blockers on preventing vasovagal syncope provide conflicting results. We sought to evaluate the effectiveness of metoprolol versus conventional treatment in preventing the recurrence of syncope in children and adolescents.
MATERIAL/METHODS: Twenty-eight children and adolescents (8 boys, 20 girls; mean age, 12+/-3 years; age range, 8-17 years) with vasovagal syncope were randomized to receive either metoprolol (metoprolol group; dosage range, 0.5-1.5 mg/kg/d) or conventional treatment (control group) for 1 year. The main outcome measure was the first recurrence of syncope beginning 2 weeks after the start of treatment. The mean follow-up was 22+/-10 months. Time to first recurrence of syncope was analyzed using Kaplan-Meier curves and compared with a log-rank test.
The 2 groups did not differ in terms of clinical characteristics. The number of syncopal episodes before tilt testing was 8+/-6 in patients in the metoprolol group and 9+/-6 in patients in the control group (P=0.150). Syncope recurred in 6 of 14 children in the metoprolol group and in 4 of 14 children in the control group. No significant between-group differences were found regarding the probability of freedom from a recurrent episode of syncope during follow-up (metoprolol vs controls, 43% vs 29%; P=0.389), as demonstrated by Kaplan-Meier curve analyses.
Recurrence of vasovagal syncope in children and adolescents treated with metoprolol is similar to that of patients treated with conventional therapy.
既往评估β受体阻滞剂预防血管迷走性晕厥效果的研究结果相互矛盾。我们旨在评估美托洛尔与传统治疗方法在预防儿童和青少年晕厥复发方面的有效性。
材料/方法：28例血管迷走性晕厥患儿和青少年（8例男孩，20例女孩；平均年龄12±3岁；年龄范围8 - 17岁）被随机分为接受美托洛尔治疗组（美托洛尔组；剂量范围0.5 - 1.5 mg/kg/d）或传统治疗组（对照组），治疗1年。主要观察指标为治疗开始2周后晕厥的首次复发。平均随访时间为22±10个月。使用Kaplan - Meier曲线分析晕厥首次复发时间，并通过对数秩检验进行比较。
两组在临床特征方面无差异。美托洛尔组患者倾斜试验前晕厥发作次数为8±6次，对照组患者为9±6次（P = 0.150）。美托洛尔组14例患儿中有6例晕厥复发，对照组14例患儿中有4例晕厥复发。Kaplan - Meier曲线分析显示，随访期间两组在无晕厥复发事件发生概率方面无显著组间差异（美托洛尔组 vs 对照组，43% vs 29%；P = 0.389）。
接受美托洛尔治疗的儿童和青少年血管迷走性晕厥复发情况与接受传统治疗的患者相似。
