冠状动脉腔内成形术中缺血和再灌注对QT离散度的影响

Effects of Ischemia and Reperfusion on QT Dispersion During Coronary Angioplasty

目的 :通过分析经皮冠状动脉腔内成形术 (percutaneous transluminal coronary angioplasty,PTCA )中缺血和再灌注时 QT离散度的变化。评价成功的 PTCA术对改善 QT离散度的临床意义。方法 :选择 2 4例冠心病患者 ,其中男 2 0例 ,女性 4例 ,平均年龄 (5 5 .5± 10 .2 )岁 ,采用光盘连续监测记录 PTCA过程中 12导联同步心电图及血压变化。分别于球囊扩张前 ,首次球囊扩张期间 ,球囊扩张后 5 s和反复多次扩张结束后 30、6 0、12 0、180 s,测定 QT间期和 RR间期 ,所有值均用 QTL C=QT+0 .15 4(1- RR)公式进行心率校正 ,QTd=QTmax- QTmin。结果 :QTd在球囊扩张期间比扩张前明显增大 (P <0 .0 5 )。 QTd在反复球囊扩张结束后的不同时间比扩张期间显著减小 (P <0 .0 1) ,同时 QTmax明显减小 ,而 QTmin不变。结论 :PTCA球囊扩张期间 ,由于产生一过性短暂的缺血使QTd增加 ,而再灌注后 ,QTd得到改善可能与缺血预适应产生的心肌保护作用有关。

Objective:The effect of percutaneous transluminal coronary angioplasty (PTCA) on QT dispersion (QTd) was evaluated in this study. Methods:QTd in 24 patients with PTCA was analysed by 12 leads ECG records simultaneously. QT and RR intervals were evaluated before, during and 5 sec after the first balloon inflation and 30, 60, 120, and 180 sec after the multiple times balloon inflation. All values were corrected by using a simple linear equation QT LC =QT+0 154(1-RR),QTd=QT max -QT min . Results:QTd increased during the first balloon inflation compared with that before the first inflation (P<0.05). QTd decreased after the multiple times inflation compared with that during the first inflation (P<0.01). QTmax significantly reduced, but QTmin did not change. Conclusion: Repeated brief episodes of myocardial ischemia during the balloon inflation increased QTd, and decrease of QTd by reperfusion may relate to ischemia preconditioning.