Horneffer P J, Healy B, Gott V L, Gardner T J
Division of Cardiac Surgery, Johns Hopkins Hospital, Baltimore, MD 21205.
Circulation. 1987 Nov;76(5 Pt 2):V39-42.
The potential for salvaging infarcting myocardium depends on the time course of the infarction process. To determine the rate of infarct evolution in an end-artery coronary preparation similar to the coronary arterial system of the human heart, each of 84 swine underwent a reversible occlusion of the left anterior descending coronary artery for varying lengths of time, after which flow was reestablished into the occluded region for either 2 or 48 hr. Infarct size was assessed by nitro blue tetrazolium (NBT) staining and confirmed by histologic examination in the 48 hr animals. The region at risk of ischemic injury was determined by injection of monastral blue dye. Infarction progressed rapidly, with a mean of 1.9 +/- 1.5% of the risk region infarcting after 15 min of occlusion, 20.3 +/- 5.7% at 30 min, 43.3 +/- 4.8% at 45 min, 59.9 +/- 2.4% at 60 min, 70.6 +/- 1.7% at 90 min, 84 +/- 2.0% at 180 min, and 88.6 +/- 2.0% after 48 hr. Although there was good correlation in infarct sizing between NBT and histologic techniques at 2 and 48 hr of reperfusion, NBT underestimated infarct size at 15 and 30 min. These data suggest that in the setting of an end-artery coronary anatomy, reperfusion must be carried out within 90 min of coronary occlusion to achieve significant salvage of infarcting myocardium, a period of time much shorter than previously suspected.
挽救梗死心肌的可能性取决于梗死过程的时间进程。为了确定在类似于人类心脏冠状动脉系统的终末动脉冠状动脉制备中梗死演变的速率，84头猪中的每一头都对左前降支冠状动脉进行了不同时长的可逆性闭塞，之后将血流重新建立到闭塞区域2小时或48小时。通过硝基蓝四氮唑（NBT）染色评估梗死面积，并在48小时的动物中通过组织学检查进行确认。通过注射蒙纳斯蓝染料确定有缺血损伤风险的区域。梗死进展迅速，闭塞15分钟后，平均有1.9±1.5%的风险区域发生梗死，30分钟时为20.3±5.7%，45分钟时为43.3±4.8%，60分钟时为59.9±2.4%，90分钟时为70.6±1.7%，180分钟时为84±2.0%，48小时后为88.6±2.0%。尽管在再灌注2小时和48小时时，NBT和组织学技术在梗死面积测量方面有良好的相关性，但在15分钟和30分钟时，NBT低估了梗死面积。这些数据表明，在终末动脉冠状动脉解剖结构的情况下，必须在冠状动脉闭塞90分钟内进行再灌注，以实现对梗死心肌的显著挽救，这一时间比之前怀疑的要短得多。
