【作者】 王才安；

【导师】 高云光；

【作者基本信息】 大理学院 ， 内科学， 2011， 硕士

【摘要】 目的：研究急性心肌缺血对体表心电图(ECG)中Tp-Te间期的影响及Tp-Te间期、校正的Tp-Te(Tp-Te/(?))和Tp-Te/QT比值与心肌梗死急性早期家兔室颤发生的相关性,为预警心肌梗死急性早期家兔室颤的发生提供依据。方法：取健康成年家兔50只,雌雄不拘,体重2.0～2.6kg,随机将家兔分为实验组(n=40)和对照组(n=10)。所有家兔均给予20%氨基甲酸己酯(5ml/kg)耳缘静脉注射麻醉,麻醉后开胸。结扎实验组家兔冠状动脉左室支,复制急性心肌梗死模型,记录开胸前、结扎前及结扎后30分钟的9导联同步ECG,根据结扎冠状动脉后30分钟内是否发生室颤分为室颤组和非室颤组。对照组家兔只开胸、穿线不结扎,记录开胸前及开胸后30分钟9导联同步ECG。测量ECG中Tp-Te间期、QT间期和R-R间期,并对QT间期、Tp-Te间期、Tp-Te/(?)校正的QT间期(QTc)和Tp-Te/QT比值进行分析。结果：1.对照组家兔术后的R-R间期、QT间期、Tp-Te间期较术前均有所延长,但差异无统计学意义(P>0.05)。2.在室颤组家兔,发生室颤前的Tp-Te间期、Tp-Te/(?)最长,且Tp-Te/QT比值达到最大,有3只家兔室颤发生于结扎冠状动脉后20-25min时段,有2只家兔室颤发生于结扎冠状动脉后20min以内时段,有1只家兔室颤发生于结扎冠状动脉后25-30min时段；在非室颤组家兔,结扎冠状动脉左室支后Tp-Te间期、Tp-Te/(?)呈延长趋势,非室颤组家兔的的Tp-Te间期、Tp-Te/(?)于结扎后25min达到最大值。3.结扎冠状动脉后实验组家兔Tp-Te间期较对照组明显延长,差异有统计学意义(41.515±4.048比33.750±4.432,P<0.05)；结扎冠状动脉后实验组家兔Tp-Te/(?)较对照组明显延长,差异有统计学意义(81.823±4.816比68.655±6.890,P<0.05)；4.结扎冠状动脉后室颤组家兔的Tp-Te间期较非室颤组家兔的Tp-Te间期延长,但差异无统计学意义(44.167±4.916比40.926±3.679,P>0.05)；结扎冠状动脉后室颤组家兔的Tp-Te/(?)较非室颤组家兔的Tp-Te/(?)明显延长,差异有统计学意义(86.191±4.524比80.852±4.386,P<0.05)；结扎冠状动脉后室颤组家兔的Tp-Te/QT比值较非室颤组家兔的Tp-Te/QT比值明显延长,差异有统计学意义(0.289±0.013比0.275±0.011,P<0.05)。结论：1.急性心肌缺血可引起Tp-Te间期延长。2. Tp-Te/(?)、Tp-Te/QT比值可作为预警心肌梗死急性早期家兔发生室颤的无创指标。3. Tp-Te/QT比值可作为消除心率影响反映Tp-Te间期相对大小的指标。更多还原

【Abstract】 Objective:The present study is to investigate the effect of actue myoeardial ischemia to Tpeak-Tend interval of surface eleetroeardiogram(ECG) and the correlation between Tpeak-Tend interval,Tp-Te/(?),Tp-Te/QT ratio and ventricular fibrillation in rabbits with early acute myocardial infarction in order to provide for warning indexes based on the occurrence of ventricular fibrillation.Method:Fifty healthy rabbits of both sexes,weighing 2.0-2.6kg, were enrolled in this study. Rabbits were randomly divided into experimental group(n=40) and control group(n=10).All rabbits were injected with 20% ethyl carbonate (5ml/kg) via ear vein and were performed thoracotomy. Left ventricular branch of coronary artery of rabbits in the experimental group were ligated to copy the model of acute myocardial infarction.The 9 leads ECG before open-chest, before ligation and the 9 leads ECG after ligation 30 minutes were reeorded. The rabbits were divided into the ventricular fibrillation group and the non-ventricular fibrillation group according to whether occurred ventricular fibrillation within coronary artery ligation 30 minutes.The rabbits in control group were opened-chest, threaded without ligation and the 9 leads ECG before open-chest and after open-chest 30 minutes were recorded.Tp-Te interval, QT interval and R-R interval in ECG was measured in order to analyse QT interval, Tp-Te interval, Tp-Te/(?), corrected QT interval (QTc) and Tp-Te/QT ratio.Result: 1. The R-R interval, QT interval, Tp-Te interval of the control group after surgery was longer versus before surgery, but the difference was not statistically significant (P> 0.05).2. The Tp-Te interval and Tp-Te/(?) of the ventricular fibrillation group was the longest and the Tp-Te/QT ratio was the maximum at the time of before ventricular fibrillation occurred.3 rabbits of the ventricular fibrillation group occurred ventricular fibrillation in 20-25min period,2 rabbits occured ventricular fibrillation in less than 20min period and a rabbit occurred ventricular fibrillation in 25-30min period after coronary artery ligation.The Tp-Te interval and Tp-Te/(?) of rabbits in the non-ventricular fibrillation group was extended trend after left ventricular branch of coronary artery ligation and the Tp-Te interval and Tp-Te/(?) of of rabbits in the non-ventricular fibrillation group rise to maximum at 25min after ligation.3. After coronary artery ligation the Tp-Te interval of rabbits in the experimental group was significantly longer than that of the control group, the difference was statistically significant (41.515±4.048 compared with 33.750±4.432, P<0.05).After coronary artery ligation the Tp-Te/(?) of rabbits in the experimental group was significantly longer than that of the control group, the difference was statistically significant (81.823±4.816 compared with 68.655±6.890, P<0.05).4. After coronary artery ligation the Tp-Te interval of rabbits in the ventricular fibrillation group was longer than that of the non-ventricular fibrillation group, but the difference was not statistically significant (44.167±4.916 compared with 40.926±3.679, P> 0.05).After coronary artery ligation the Tp-Te/(?) of rabbits in the ventricular fibrillation group was significantly longer than that of the non-ventricular fibrillation group, the difference was statistically significant (86.191±4.524 compared with 80.852±4.386, P<0.05).After coronary artery ligation the Tp-Te/QT ratio of rabbits in the ventricular fibrillation group was significantly longer than that of the non-ventricular fibrillation group, the difference was statistically significant (0.289±0.013 compared with 0.275±0.011, P<0.05).Conclution:1. Acute myocardial ischemia can cause Tp-Te interval prolongation.2. Tp-Te/(?) and Tp-Te/QT ratio can be used as non-invasive indexes of warning ventricular fibrillation occurred in rabbits with early acute myocardial infarction.3. Tp-Te/QT ratio can be used as an index of reflect the Tp-Te interval relative size by eliminate heart rate influence.更多还原