老年急性心肌梗死后梗死相关动脉再灌注对QT离散度的影响

目的了解老年急性心肌梗死(AMI)后梗死相关动脉(IRA)早期静脉溶栓再灌注或冠状动脉内支架置入术对QT离散度(QTd)的影响。方法对58例老年AMI患者(AMI组)予以静脉内溶栓,溶栓后选择性冠状动脉造影,对判定为心肌梗死溶栓试验性疗法(TIMI)2级以下者,部分行冠状动脉内支架置入术。溶栓前后测量分析QTd,并与48例冠状动脉造影正常的老年人(对照组)和50例健康体检非老年患者(非老年组)进行对照。结果AMI组溶栓前与对照组和非老年组间QTd有显著性差异(P<0.01);静脉溶栓后冠状动脉造影显示IRA血流达到TIMI 2~3级者,溶栓后2 h QTd显著降低,而IRA未开通者其QTd始终保持较高水平。16例溶栓前有室性心律失常者其QTd明显高于无心律失常者(P<0.05),结论IRA早期再灌注可使QTd显著降低,可减少恶性心律失常的发生。

Effects of reperfusion of infarct-related artery after intravenous thrombolysis in AMI on QT dispersion

Objective To evaluate the effect of early reperfusion of infarct-related artery(IRA) after intravenous thrombolysis in old patients on QT dispersion(QTd).Methods Fifty-eight acute myocardial infarction(AMI)old patients and 48 healthy old people used as control group and 50 healthy non-old people were studied.Coronary artery angiography was done after intravenous thrombolytic therapy in AMI patients.Twenty-three patients with IRA under TIMI 2 flow had received implantation of coronary stents.QTd was measured before and after thrombolysis.Results QTd was significantly prolonged in patients with AMI before thrombolysis compared with control group and healthy non-old people group(P<0.01).At 2nd hour after intravenous thrombolysis,QTd decreased significantly in TIMI 2～3 grade group,and remained unchanged in under TIMI 2 grade group.Sixteen AMI patients had ventricular arrhythmias before thrombolysis and the QTd was significantly longer in these patients as compared with those without arrhythmia(P<0.05).Conclusions Successful early reperfusion of IRA is associated with the reduction of QTd and decrease in risk of ventricular arrhythmia in AMI patients.