直立性高血压儿童卧位、立位心电图T波和ST段振幅变化及其临床意义

T wave and ST segment amplitude changes in the supine and standing electrocardiograms of children with orthostatic hypertension and their clinical significance

目的探讨直立性高血压(OHT)儿童卧位与立位心电图T波和ST段振幅变化及其临床意义.方法选取确诊为OHT患儿49例为OHT组,同期按年龄与性别匹配43例健康儿童为对照组.测量两组卧位与立位12导联心电图心率、各导联T波和ST段振幅,比较同组卧位和立位T波振幅、ST段振幅,并比较两组卧位、立位T波振幅差和ST段振幅差.结果对照组aVR、V1、V4~V6导联T波振幅立位较卧位降低(P<0.05),V4、V5导联ST段振幅立位较卧位增加(P<0.05).OHT组Ⅱ、aVR、aVF、V4~V6导联T波振幅立位较卧位降低(P<0.05),Ⅱ导联ST段振幅立位较卧位增加(P<0.05).OHT组Ⅱ、V6导联立位、卧位T波振幅差较对照组增大(均P<0.05).V6导联卧位、立位T波振幅差对OHT有诊断价值(P<0.05),V6导联T波振幅差最佳截断值为0.105 mV,灵敏度为72.10%,特异度为57.10%.结论 V6导联卧位、立位T波振幅差对OHT儿童具有一定的诊断价值.

Objective To examine the changes in T wave and ST segment amplitude in the supine and standing electrocardiograms(ECG)of children with orthostatic hypertension(OHT)and to determine their clinical significance.Methods A total of 49 children with OHT were included in the OHT group.Forty-three age-and sex-matched healthy children were included in the control group.Heart rate and T wave and ST segment amplitude were measured in both groups.T wave amplitude and ST segment amplitude in supine ECG were compared with those in standing ECG within each group.The differences in supine vs standing T wave amplitude and ST segment amplitude were compared between the OHT and control groups.Results In the control group,T wave amplitude in leads aVR,V1,and V4-V6 were significantly lower in standing ECG than in supine ECG(P<0.05);ST segment amplitude in leads V4 and V5 were significantly higher in standing ECG than in supine ECG(P<0.05).In the OHT group,T wave amplitude in leads II,aVR,aVF,and V4-V6 were significantly lower in standing ECG than in supine ECG(P<0.05);ST segment amplitude in lead Ⅱ was significantly higher in standing ECG than in supine ECG(P<0.05).The differences in T wave amplitude in lead Ⅱ and V6 between supine and standing ECG were significantly higher in the OHT group than in the control group(P<0.05).Difference in T wave amplitude in lead V6 between supine and standing ECG was a significant diagnostic marker for OHT(P<0.05).This marker had 72.10%sensitivity and 57.10%specificity for the diagnosis of OHT at the optimal cut-off value of 0.105 mV.Conclusions Difference in T wave amplitude in lead V6 between supine and standing ECG has certain diagnostic value for OHT.