Kern K B, Hilwig R W, Warner A, Basnight M, Ewy G A
Department of Medicine, University of Arizona College of Medicine, Tucson.
Am Heart J. 1995 Apr;129(4):650-5. doi: 10.1016/0002-8703(95)90310-0.
The usefulness of intravenous beta-adrenergic receptor blockade in limiting infarct size when neither reperfusion nor collateral flow occurs is unknown. The effect of intravenous metoprolol on limiting myocardial infarct size was therefore examined in a nonreperfused porcine model. Closed-chest techniques were used to occlude the left anterior descending coronary artery, after which animals were randomized at 20 minutes to receive intravenous metoprolol, 0.75 mg/kg, or placebo. Infarct size examined at 5 hours with Evans blue and triphenyltetrazolium staining techniques was expressed as a percentage of total ventricular myocardium at ischemic risk. This percentage was not significantly different between the groups (84% +/- 5% with metoprolol vs 90% +/- 4% with placebo; p = 0.4). Myocardial infarct size was not significantly decreased at 5 hours by early administration of intravenous metoprolol when the infarct artery remained occluded and collateral flow was minimal.
在既未发生再灌注也无侧支血流的情况下，静脉注射β - 肾上腺素能受体阻滞剂对限制梗死面积的作用尚不清楚。因此，在一个未进行再灌注的猪模型中研究了静脉注射美托洛尔对限制心肌梗死面积的影响。采用闭胸技术阻断左前降支冠状动脉，之后在20分钟时将动物随机分组，分别接受静脉注射美托洛尔（0.75mg/kg）或安慰剂。采用伊文思蓝和三苯基四氮唑染色技术在5小时时检测梗死面积，并表示为处于缺血风险的整个心室心肌的百分比。两组之间该百分比无显著差异（美托洛尔组为84%±5%，安慰剂组为90%±4%；p = 0.4）。当梗死动脉仍被阻塞且侧支血流极少时，早期静脉注射美托洛尔在5小时时并未显著减小心肌梗死面积。
