急性心肌梗死患者QT变异度和QT变异系数

目的:描述急性心肌梗死(AMI)患者心室复极变异度和变异系数。方法:55例AMI患者和60例正常人接受24 hHolter检测,人工编辑QRS-T波群模板,计算机辅助测定24 h和每小时平均QT间期、标准差。计算24 h、白天、夜间QT间期标准差(即QT变异度,QTV)和QT变异系数(QTCV)。结果:组内比较,正常对照组QTV昼夜呈动态变化,有明显差别(P<0.01),AMI组则不显著;组间比较,两组QTV均在7:00～8:00达最大值,但AMI组明显低于正常组,且AMI组24 h和白天QT变异度也显著低于正常对照组(P<0.01),夜间则无明显差异。结论:AMI患者全天和白天QTV和QTCV显著降低,失去正常人昼夜规律,反映了AMI患者心室复极电活动紊乱,可能与交感神经受损有关。QTV和QTCV可能是AMI患者自主神经受损和电生理紊乱的新指标,且QTCV较QTV更有统计学价值。

QT variability and QT coefpilient of variation in acnte myocardial infarction(AMI)

Objective:To study QT variability in acute myocardial infarction(AMI) Methods:Fifty -five patients with AMI and sixty control subjects served as the study population. They were examined by 24 h Holter monitoring. The computer analyzed and computed the mean and standard deviation of QT interval and RR interval. We make the deviation of QT interval as the QT variability (QTV). The ratio of QTV and QT interval mean is regarded as QT co-efficient of variation(QTCV). Results:The QTV and QTCV in the control group were dynamically changing during 24 h.and the difference between day and night was distinct. While the trend of QTV in AMI group during 24 h was smooth.and the difference of QTV between day and night was not apparent. QTV of two group reached the summit at 7:00-8:00. But QTV of AMI in such period was lower than the control group. And QTV and QTCV of AMI in 24 h and day were lower than the control group.Conclustiion:QTV and QTCV of AMI decreased in 24 h and day.and the difference between day and night was not distinct .compared with the control group. QTV and QTCV reflected the confusion of myocardial electricities, which was perhaps concerned with the injury of symatheticfiber in AMI. QTV and QTCV conle be a new norm mirrorig vegetable fibers and myocardial electrilitiesy. Moreover,QTCVwas superior to QTV in statistics.