QT间期离散度对儿童及青少年心脏抑制型血管迷走性晕厥的诊断效能及预后估测价值

目的:探讨QT间期离散度(QT interval dispersion,QTd)对儿童及青少年心脏抑制型血管迷走性晕厥(cardioinhibitory vasovagal syncope,VVS-CI)的诊断效能及预后估测价值。方法:选择2010年7月至2020年1月因晕厥或晕厥先兆在中南大学湘雅二医院儿童晕厥专科门诊首次就诊或住院、明确诊断为VVS-CI的儿童及青少年80例为VVS-CI组,匹配同期在本院进行健康体检的儿童及青少年80例为对照组。测量两组基础状态下12导联心电图QT间期。结果:(1)两组比较:VVS-CI组较对照组心率降低( P<0.05),最大QT间期(maximum QT interval,QTmax)、最小QT间期(minimum QT interval,QTmin)、QTd、校正最大QT间期(corrected maximum QT interval,QTcmax)、校正QT间期离散度(corrected QT interval dispersion,QTcd)延长( P<0.05)。随访84(45,127)d,无反应组较有反应组QTmax、QTd、QTcmax、校正最小QT间期(corrected minimum QT interval,QTcmin)、QTcd延长( P<0.05)。(2)诊断效能:QTmax、QTmin、QTd、QTcmax、QTcd对儿童及青少年VVS-CI有诊断价值( P<0.001)。QTd的曲线下面积(area under the curve,AUC)最大(0.914),最佳截断值为28.50 ms,诊断VVS-CI的敏感度为86.30%,特异度为84.95%。(3)预后估测价值:QTmax、QTd、QTcmax、QTcmin、QTcd对儿童及青少年VVS-CI预后有估测价值( P<0.05或0.01)。QTd的AUC最大(0.906),最佳截断值为34.50 ms,预测对VVS-CI干预有反应的敏感度为90.00%,特异度为82.35%。 结论:心电图QTd对儿童及青少年VVS-CI的诊断及预后有较好的估测价值。

Diagnostic efficacy and prognostic evaluation value of QT interval dispersion in children and adolescents with cardioinhibitory

Objective To study the diagnostic efficacy and prognostic evaluation value of QT interval dispersion(QTd)in children and adolescents with cardioinhibitory vasovagal syncope(VVS-CI).Methods From July 2010 to January 2020,80 children and adolescents who received their first visit or admission to the Pediatric Syncope Clinic of The Second Xiangya Hospital of Central South University and definite diagnosed of VVS-CI due to syncope or presyncope were selected as the VVS-CI group,meanwhile,80 children and adolescents who had physical examination in the hospital were selected as the control group.QT interval were measured by 12-lead electrocardiogram at the baseline.Results(1)Comparison between the two groups:Compared with the control group,the VVS-CI group had a significantly lower heart rate(P<0.05)and significantly longer QT interval,such as the maximum QT interval(QTmax),minimum QT interval(QTmin),QTd,corrected maximum QT interval(QTcmax)and corrected QT interval dispersion(QTcd)(P<0.05).After follow-up 84(45,127)days,compared with the responsive group,the non-responsive group had a significantly longer QT interval,such as QTmax,QTd,QTcmax,corrected minimum QT interval(QTcmin)and QTcd(P<0.05).(2)Diagnostic efficiency:QTmax,QTmin,QTd,QTcmax and QTcd had a certain diagnostic value in children and adolescents with VVS-CI(P<0.001).QTd had the largest area under the curve(AUC)(0.914),and had a sensitivity of 86.30%and a specificity of 84.95%at the optimal cut-off value of 28.50 ms for VVS-CI diagnosis.(3)Prognostic evaluation value:QTmax,QTd,QTcmax,QTcmin,QTcd had an estimated value for the prognosis of VVS-CI in children and adolescents(P<0.05 or 0.01).QTd had the largest AUC(0.906)and the best cut-off value was 34.50 ms,the sensitivity to predict response to VVS-CI intervention was 90.00%,and the specificity was 82.35%.Conclusion QTd of electrocardiogram has a good estimation value in the diagnosis and prognosis of VVS-CI in children and adolescents.