Wilson J L, Scheel K W
Anat Rec. 1982 Oct;204(2):113-22. doi: 10.1002/ar.1092040204.
This study was designed to quantitate and describe the incidence and magnitude of myocardial infarction in the canine heart following acute and gradual occlusion of the circumflex or right coronary arteries. In animals with acute occlusion, the circumflex artery was ligated just distal to the bifurcation of the left coronary artery for 4 hr (seven dogs). Gradual occlusion was produced by placing an Ameroid occluder on the circumflex artery for 1 month (nine dogs), 3 months (nine dogs), and 5 months (eight dogs) and on the right coronary artery for 3 months (nine dogs). Ten dogs served as controls. At the end of the experiments the dogs were sacrificed, and identification of myocardial infarction was made with an enzyme-mapping technique in dogs with acute occlusion and with histological methods in dogs with gradual occlusion. The volume of ventricular infarction was determined with the use of an Apple II Computer and graphics tablet. After 3 months, gradual occlusion of the right coronary artery produced a 22% incidence of infarction which was significantly less (P less than .01, chi 2) than the 67% incidence observed with 3 months of gradual circumflex occlusion. The average infarct volume produced by gradual right coronary occlusion was 0.94 + 0.69%. The average volume of left ventricular infarction in animals with circumflex acute occlusion was 15.6% + 6.6 and the incidence of infarction was 100%. With gradual occlusion of the circumflex artery for 1, 3, and 5 months, average left ventricular infarction was 2.02 +/- 1.01%, 3.13 +/- 1.53%, and 2.96 +/- 1.35%, respectively. There were no significant differences in the amount of damage observed among the three groups with gradual occlusion, and the average incidence of infarction for these three groups was 76%. In the 1-, 3- or 5-month animals with circumflex occlusion, no additional areas of necrosis subsequent to the original damage were found, indicating that infarction is a single event in this model of gradual occlusion. These results suggest that infarct size is determined primarily by factors at the time of total occlusion and that gradual occlusion allows sufficient time for collateral growth, thereby limiting the extent of myocardial injury.
本研究旨在定量并描述犬心脏在急性和逐渐闭塞左旋支或右冠状动脉后心肌梗死的发生率及严重程度。在急性闭塞的动物中，将左旋支动脉在左冠状动脉分叉远端结扎4小时（7只犬）。通过在左旋支动脉上放置阿梅罗德闭塞器1个月（9只犬）、3个月（9只犬）和5个月（8只犬）以及在右冠状动脉上放置3个月（9只犬）来实现逐渐闭塞。10只犬作为对照。实验结束时处死犬，对于急性闭塞的犬用酶标技术鉴定心肌梗死，对于逐渐闭塞的犬用组织学方法鉴定。使用苹果II计算机和图形输入板确定心室梗死体积。3个月后，右冠状动脉逐渐闭塞产生梗死的发生率为22%，显著低于（P＜0.01，卡方检验）左旋支动脉3个月逐渐闭塞时观察到的67%的发生率。右冠状动脉逐渐闭塞产生的平均梗死体积为0.94 + 0.69%。左旋支急性闭塞动物的左心室梗死平均体积为15.6% + 6.6，梗死发生率为100%。左旋支动脉逐渐闭塞1个月、3个月和5个月时，左心室平均梗死分别为2.02 +/- 1.01%、3.13 +/- 1.53%和2.96 +/- 1.35%。在逐渐闭塞的三组中观察到的损伤量无显著差异，这三组的平均梗死发生率为76%。在左旋支闭塞1个月、3个月或5个月的动物中，未发现原始损伤后有额外的坏死区域，表明在这种逐渐闭塞模型中梗死是单一事件。这些结果表明梗死大小主要由完全闭塞时的因素决定，并且逐渐闭塞为侧支循环生长留出了足够时间，从而限制了心肌损伤的程度。
