Neill W A, Nakornchai V, Oxendine J, Paul M S
Circulation. 1979 Feb;59(2):280-5. doi: 10.1161/01.cir.59.2.280.
Acute left circumflex coronary artery (LC) occlusion in conscious dogs caused marked ischemia in the myocardium supplied by the occluded artery, as judged by the radioactive microsphere technique for determining blood flow distribution. With the chest open, LC pressure distal to the occlusion fell to 21 +/- 1.9% of aortic pressure. By 8 weeks after gradual LC occlusion with an ameroid constrictor, collateral development had restored coronary blood flow distribution to near-normal under basal conditions and during pacing, at a heart rate of 200 beats/min. The only evidence for ischemia was in the subepicardium within the distribution of the unoccluded left anterior descending artery, which provided the extra collateral blood flow. Distal LC pressure was 70 +/- 1.7% of aortic pressure. Propranolol 160 mg orally every 6 hours for 8 weeks had no detectable effect on coronary collateral development, as judged by blood flow distribution or distal LC pressure. The only significant difference for the propranolol dogs was a slight transmural shift away from the subendocardium in the left anterior descending region.
通过放射性微球技术测定血流分布来判断，清醒犬急性左旋冠状动脉（LC）闭塞会导致闭塞动脉所供血的心肌出现明显缺血。打开胸腔后，闭塞远端的LC压力降至主动脉压力的21±1.9%。在用阿梅洛依德缩窄器逐渐闭塞LC后8周，在基础状态和起搏时（心率200次/分钟），侧支循环的发展已使冠状动脉血流分布恢复到接近正常。缺血的唯一证据存在于未闭塞的左前降支动脉供血区域的心外膜下，该动脉提供了额外的侧支血流。远端LC压力为主动脉压力的70±1.7%。每6小时口服160毫克普萘洛尔，持续8周，根据血流分布或远端LC压力判断，对冠状动脉侧支循环的发展没有可检测到的影响。普萘洛尔组犬唯一显著的差异是左前降支区域内膜下有轻微的透壁性偏移。
