The Microvascular Unit Size for Fractal Flow Heterogeneity Relevant for Oxygen Transport
Blood flow is heterogeneously distributed in the myocardium. The width of this distribution depends on the spatial resolution of the flow measurement. Flow heterogeneity has been described by a fractal relation: the relative dispersion (standard deviation/mean) of the measured flow distribution increases with the spatial resolution of the measurement via a power law (Bassingthwaighte et al., 1989). The dependence of the dispersion of the flow distribution on spatial resolution has also been explained with a fractal vascular network model (Van Beek et al., 1989). Both types of fractal model imply that the heterogeneous flow is not distributed randomly, but that flow shows spatial correlation over large distances.
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