Determinants of the Pressure-Flow Relation in the Coronary Vasculature

摘要

This paper reviews two series of experiments concerning coronary hemodynamics and offers a biomedical theory of their formation. The first series was performed on conscious resting dogs instrumented for pressure and flow measurements. Pressure-flow relations showed a positive pressure intercept at zero flow and a slope which depended on vasomotor tone and extravascular compressive forces. These results were reconfirmed in the second series, which was performed on swine hearts isolate in situ. In the swine heart, pharmacological intervention with barium chloride and acetylcholine demonstrated the controlling influence of separate mechanical parameters. A theoretical interpretation of these results is presented in terms of the vascular waterfall hypothesis which relates these hemodynamic phenomena to the physics of collapsible tubes.