Tp-Te间期对于儿童室性早搏的意义

目的：探讨Tp-Te间期对于儿童室性早搏（VPC）危险分层的意义。方法：将120例VPC患儿按病因分成良性室早组、室性并行心律组和器质性室早组，每组各40例，另选取40例行健康体检儿童为正常对照组。比较4组间心电图V3、V4、V5导联的Tp-Te间期、Tp-Te/QT比率的差异。结果：V3导联显示器质性室早组Tp-Te间期较其余各组均延长（P<0.05）；V4导联显示良性室早组Tp-Te间期仅较正常对照组与器质性室早组缩短（P<0.05）；V5导联显示器质性室早组Tp-Te间期仅较良性室早组延长（P<0.05）。V3~V5导联均显示器质性室早组Tp-Te/QT比率较其余各组明显升高，差异均有统计学意义（均P<0.05）；同时V4和V5导联显示Tp-Te/QT比率在室性并行心律组与良性室早组之间差异均有统计学意义（均P<0.05）。结论：Tp-Te间期容易受心率的影响，在儿童时期用于VPC危险分层时，价值不大；而Tp-Te/QT比率可以作为临床儿童VPC危险分层的重要无创指标，值得进一步研究。

Significance of Tp-Te interval for risk stratification of ventricular premature contractions in children

OBJECTIVE: To investigate the significance of Tp-Te interval for risk stratification of ventricular premature contractions (VPC) in children. METHODS: A total of 120 children with VPC were divided into benign VPC (n=40), organic disease (n=40) and ventricular parasystole groups (n=40) according to the etiology of VPC; another 40 children who underwent physical examination were selected as the normal control group. The four groups were compared in terms of Tp-Te intervals and Tp-Te/QT ratios in leads V3, V4 and V5. RESULTS: The Tp-Te interval in lead V3 was significantly longer in the organic disease group than in the other groups (P<0.05), the benign VPC group had a significantly shorter Tp-Te interval in lead V4 than the normal control and organic disease groups (P<0.05), and the organic disease group had a significantly longer Tp-Te interval in lead V5 than the benign VPC group (P<0.05). The Tp-Te/QT ratios in leads V3-V5 were significantly higher in the organic disease group than in the other groups (P<0.05). The Tp-Te/QT ratios in leads V4 and V5 showed significant differences between the ventricular parasystole and benign VPC groups (P<0.05). CONCLUSIONS: Tp-Te interval is susceptible to changes in heart rate, and it is of little value for the risk stratification of VPC in children. Tp-Te/QT ratio, however, may be used as an important non-invasive index for clinical risk stratification of VPC in children and is worthy of further study.