Akaishi M, Schneider R M, Mercier R J, Naccarella F F, Agarwal J B, Helfant R H, Weintraub W S
J Am Coll Cardiol. 1985 Jul;6(1):104-12. doi: 10.1016/s0735-1097(85)80260-6.
To develop a quantitative relation between the overall severity of acute ischemia and left ventricular global and regional function, two minor axis internal diameters and myocardial wall thickness were determined using ultrasonic crystals in 10 open chest dogs with carotid-left anterior descending artery cannulation. The overall extent of ischemia produced by graded stenosis of the cannulation system was estimated by total myocardial blood flow deficit, calculated using radioactive microspheres and a balloon-reservoir perfusion technique permitting precise separation of ischemic from nonischemic tissue. Although cardiac output and left ventricular stroke work were maintained through chamber enlargement until total myocardial blood flow deficit was about 10%, ejection indexes of left ventricular function decreased progressively with increasing ischemia and correlated inversely with total myocardial blood flow deficit (r = -0.55 to -0.73). Ejection indexes of left ventricular global function correlated directly with regional function in the ischemic zone (r = 0.67 to 0.83), although global function decreased at a far slower rate than regional contraction during progressive coronary stenosis with an ischemic region comprising about 25% of total left ventricular weight. During myocardial ischemia, regional dysfunction resulted in progressive global contractile dysfunction; left ventricular hemodynamic status was maintained until ischemia was severe.
为了建立急性缺血的总体严重程度与左心室整体及局部功能之间的定量关系，使用超声晶体对10只开胸并进行颈动脉 - 左前降支动脉插管的犬测定了两个短轴内径和心肌壁厚度。插管系统分级狭窄所产生的缺血总体范围通过总心肌血流不足来估计，总心肌血流不足是使用放射性微球和气囊 - 储液器灌注技术计算得出的，该技术能够精确区分缺血组织和非缺血组织。尽管通过心室扩大维持心输出量和左心室搏功，直到总心肌血流不足约为10%，但随着缺血程度增加，左心室功能的射血指数逐渐降低，且与总心肌血流不足呈负相关（r = -0.55至-0.73）。左心室整体功能的射血指数与缺血区的局部功能直接相关（r = 0.67至0.83），尽管在缺血区域占左心室总重量约25%的进行性冠状动脉狭窄过程中，整体功能下降的速度远比局部收缩慢。在心肌缺血期间，局部功能障碍导致进行性整体收缩功能障碍；在缺血严重之前，左心室血液动力学状态得以维持。
