犬冠状动脉狭窄程度与血液动力学改变的相关分析

Correlation between the degree of stenosis of coronary artery and hemodynamie changes in dog

冠脉狭窄可以引起血液动力学改变,这种改变与狭窄程度和心肌缺血的关系尚不清楚。本文用微米缩窄器在犬冠状动脉定量地造成狭窄,观察了主动脉压(MAP)、狭窄远端小动脉压(DCP)、ECG等的变化,其结果如下:冠脉狭窄在85%以上,冠脉流量(CBF)出现减少。当CBF减少到1/3时,MAP开始降低,在CBF减少到1/5时,心率下降,ECG中ST段出现抬高。冠脉狭窄达85%以上,DCP与CBF呈正相关(P<0.01),而MAP与CBF无相关(P>0.05)。DCP与MAP不相关(P>0.05)。狭窄两端压差(_△P)与CBF有曲线关系,其方程是CBF=37.64-0.42_△P-0.0006(_△P)~2。

Coronary artery stenosis caused a hemodynamic change, but the relationship between this change and coronary stenosis (or cardiac ischemia)was unclear. This experiment was made on coronary circumlex artery or LAD. The coronary stenosiswas produced by a micrometer constrictor. Mean aortic pressure (MAP), distal Coronary pressure (DCP), coronary blood flow (CBF) and ECG were observed. The results were as follows: CBF was decreased when coronary artery stenosis was higher than 85%, then MAP decreased while CBF decreased to one third of its value, finaly heart rate (HR) decreased and ST segment elevated while CBF decreased to one fifth of its value. After coronary artery stenosis was higher than 85%, it showed a positive correlation between DCP and CBF, (P<0.01) and that there was not any correlation between MAP and CBF or DCP and MAP. There was a curvaceous relation between the pressure drop (_△P=MAP-DCP) and CBF [CBF=37.63-0.42_△P-0.0006(_△p^2)].