Barclay K D, Klassen G A, Young C
School of Health and Human Performance, Dalhousie University, Halifax, Nova Scotia, Canada.
Microcirculation. 2000 Oct;7(5):335-46.
To determine whether red cell movement, as measured by laser Doppler velocimetry, in the capillary net of the beating heart is chaotic.
Using two dog hearts, in situ red blood cell flux was measured at many sites. Simultaneously, epicardial arterial flow and left ventricular pressure were recorded via transit-time flowmeter and catheter manometer, respectively. The presence or absence of chaos was tested by two methods: Lyapunov exponents and correlation dimension.
For capillary red cell flux, the Lyapunov was strongly positive at most sites. It was less so for coronary arterial flow and least for left ventricular pressure. Correlation dimension calculation was less able to distinguish the presence or absence of chaos in capillary red cell tissue flux, coronary arterial flow, and left ventricular pressure.
Capillary red cell flux (movement of red cells in capillaries) is nonlinear, (i.e., chaotic). This complexity suggests that the primary control for oxygen delivery to cardiac myocytes by red blood cells resides in the microcirculation. Also, capillary red cell flux is bifractal, suggesting an ordering of control.
通过激光多普勒测速法测定跳动心脏毛细血管网中的红细胞运动是否呈混沌状态。
使用两颗犬心脏，在多个部位测量原位红细胞通量。同时，分别通过渡越时间流量计和导管压力计记录心外膜动脉血流和左心室压力。采用两种方法测试混沌的存在与否：李雅普诺夫指数和关联维数。
对于毛细血管红细胞通量，多数部位的李雅普诺夫指数呈强正值。冠状动脉血流的该指数较小，左心室压力的最小。关联维数计算在区分毛细血管红细胞组织通量、冠状动脉血流和左心室压力中混沌的存在与否方面能力较弱。
毛细血管红细胞通量（红细胞在毛细血管中的运动）是非线性的，即呈混沌状态。这种复杂性表明，红细胞向心肌细胞输送氧气的主要控制机制存在于微循环中。此外，毛细血管红细胞通量是双分形的，提示存在控制的有序性。
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