Collateral conductance changes during a brief coronary occlusion in awake dogs.
Collateral conductance changes during a brief coronary occlusion in awake dogs.
复制标题
清醒狗短暂冠状动脉闭塞期间侧支电导发生变化。
DOI：
10.1161/01.cir.72.1.225
复制
发表时间：
1985
期刊：
影响因子：
37.8
通讯作者：
GreenfieldJr,JC
中科院分区：
文献类型：
--
作者：
Brazzamano,S;Fedor,JM;Rembert,JC;GreenfieldJr,JC
在长期使用仪器的清醒狗中评估单次冠状动脉突然闭塞过程中冠状动脉侧支循环的功能。研究是在近端左旋支冠状动脉部分狭窄刺激狗的侧枝发育后约两周进行的。连续测量从中央主动脉到远端回旋支冠状动脉的压降。在控制条件下，在单次突然完全回旋支闭塞的 30 秒和 4 分钟时，通过放射性微球技术测定心肌血流量。冠状动脉侧支传导率计算为平均侧支血流量除以平均压降。在发育出侧支血管的狗中注意到以下情况：在冠状动脉闭塞期间，平均远端回旋支冠状动脉压力从 42 +/- 9 增加到 49 +/- 10 mm Hg（p 小于或等于 0.01）；平均侧支流量从 0.78 +/- 0.30 增加到 0.84 +/- 0.33 ml/min/g（p 小于或等于 0.05）；心内膜/心外膜流量比从 0.77 +/- 0.36 增加到 1.04 +/- 0.25（p 小于或等于 0.01）；冠状动脉侧支电导从 0.017 +/- 0.017 显着增加至 0.021 +/- 0.021 (ml/min/g)/mm Hg（p 小于或等于 0.005）。这些数据表明，在主要冠状动脉短暂闭塞期间，未成熟的冠状动脉侧支通道在闭塞后不会立即达到最大功能。相反，冠状动脉侧支传导随时间增加，并且可能与心肌透壁灌注的改善有关。
Function of the coronary collateral circulation during the course of a single abrupt coronary occlusion was evaluated in awake dogs instrumented over the long term. Studies were performed approximately 2 weeks after collateral development had been stimulated in the dogs by partial stenosis of the proximal left circumflex coronary artery. The pressure drop from the central aorta to the distal circumflex coronary artery was measured continuously. Under control conditions and at 30 sec and 4 min of a single abrupt complete circumflex occlusion, myocardial blood flow was determined by a radioactive microsphere technique. Coronary collateral conductance was calculated as mean collateral blood flow divided by the mean drop in pressure. The following was noted in dogs that developed collateral vessels: during the coronary occlusion, mean distal circumflex coronary pressure increased from 42 +/- 9 to 49 +/- 10 mm Hg (p less than or equal to .01); mean collateral flow increased from 0.78 +/- 0.30 to 0.84 +/- 0.33 ml/min/g (p less than or equal to .05); the endocardial/epicardial flow ratio increased from 0.77 +/- 0.36 to 1.04 +/- 0.25 (p less than or equal to .01); and the coronary collateral conductance increased significantly from 0.017 +/- 0.017 to 0.021 +/- 0.021 (ml/min/g)/mm Hg (p less than or equal to .005). These data suggest that during a brief occlusion of a major coronary artery, immature coronary collateral channels do not reach maximal function immediately after the occlusion. Rather, coronary collateral conductance increases with time and may be associated with improved transmural perfusion of the myocardium.