Distribution and control of coronary microvascular resistance.

Coronary blood flow depends upon the vascular resistance distributed non-uniformly within the coronary microcirculation. Coronary microvascular resistance is governed by metabolic, myogenic, endothelial and neurohumoral influences. A number of these control mechanisms interact locally within a microvascular segment. In addition, these control mechanisms occupy differing longitudinal response gradients, a feature which maximizes their potential for the synergistic control of flow.