急性心肌梗死恢复期PTCA及支架置入术对QT离散度的影响

Effects of successful percutaneous transluminal coronary angioplasty or stent implantation in the recovery period after acute myocardial infarction on QT dispersion

目的 观察急性心肌梗死 (AMI)恢复期 (2～ 4周 )行经皮冠状动脉腔内成形术 (PTCA)及支架置入术对QT离散度 (QTd)的影响。方法 选择 5 7例AMI恢复期的患者 ,分别记录PTCA及支架置入术前 1d ,术后 1h的 12导联同步心电图 ,测量QTd及校正的QTd(QTcd) ,并与 86例同期行冠状动脉造影结果正常者进行对照。结果 AMI组行PTCA及支架置入术前最大QT间期 (QTmax) ,最小QT间期 (QTmin) ,QTd及QTcd均较对照组明显增大 ,差异有显著性。前壁与下壁AMI之间上述指标差异无显著性。成功的PTCA及支架置入术后QTmax,QTmin,QTd及QTcd比术前明显缩短 ,两者相比差异有显著性。而单纯行冠状动脉造影对QT离散度无明显影响。结论 AMI患者QTd及QTcd显著高于正常人 ,而AMI恢复期成功的PTCA及支架置入术可使增加的QTd及QTcd显著缩短 ,从而减低AMI后恶性心律失常和心源性猝死的发生率 ,改善患者的远期预后。

Objective To evaluate the changes of QT dispersion (QTd) after successful percutaneous transluminal coronary angioplasty (PTCA) or stent implantation during the recovery period after acute myocardial infarction (AMI).Methods We studied 57 AMI patients who underwent PTCA or stent implantation and 86 normal coronary artery subjects used as control. Maximal and minimal QT interval (QT max and QT min) and QTd (QTd=QT max-QT min) were measured using 12-lead electrocardiography within 1 d before and 1 h after PTCA and stent implantation or coronary angiography.Results QTd and corrected QT dispersion (QTcd) were significantly prolonged in patients with AMI compared with control group. There was no significant difference in QTd and QTcd between anterior AMI and inferior one. QT max, QTc max, QTd and QTcd after PTCA or stent implantation were significantly decreased.Conclusion QTd and QTcd were significantly decreased after successful PTCA or stent implantation which were performed during the recovery period of AMI, which shows it can produce beneficial effects in decreasing the risk of ventricular arrhythmia and reducing mortality in AMI patients.