缺血预适应对短期冬眠心肌动物模型QT离散度及心律失常的影响

Effect of ischemic preconditioning on QT dispersion and arrhythmia scores in short-term hibernating myocardium

目的观察缺血预适应(IPC)对短期冬眠心肌(SHM)动物模型心律失常的发生情况及QT离散度(QTd)的影响。方法12只中国小型家猪应用闭胸法制备SHM模型,随机分为2组:①对照组(n=6),只制备SHM模型;②缺血预适应组(IPC组,n=6),制备SHM模型前给予缺血5 min、再灌注5 min处理,重复2次。于基础状态、冠状动脉狭窄后10、30、60、120 min记录同步12导联心电图,计算QTd。同时,记录实验过程中心律失常的发生情况,计算心律失常评分。结果2组家猪基础状态时QTd差异无显著性(P>0.05),冠状动脉狭窄后各时间点QTd较基础状态均明显增加(P<0.01),但IPC组较对照组明显降低(P<0.01)。IPC组心律失常评分较对照组明显降低(P<0.01)。结论IPC明显降低SHM动物模型QTd的增加,并可减少心律失常的发生。

Objective To observe the effects of ischemic preconditioning on the QT dispersion （QTd） and incidence of arrhythmias in an animal model of short - term hibernating myocardium （SHM）. Methods 12 little domestic Chinese pigs used to establish the model of SHM by interventional method （closed -chest）, were divided into 2 groups at random ： the control group （ CON group, n = 6） and the ischemic preconditioning group （ IPC group, n = 6）. IPC was conducted by making 2 cycles of 5 - min ischemia followed by 5 - min reperfusion before the establishment of model. The 12 - lead electrocardiogram recording was taken at different time points to calculate QTd and grade arrhythmia. Results The QTd were similar at the basal line in the two groups, and increased significantly at all the time points after the coronary artery was stenosed. The QTd was much lower in IPC group than in CON group; the arrhythmia score was lower in IPC group than in CON group. Conclusion IPC can reduce the increment of QTd and decrease the incidence of arrhythmia in SHM model.