title: Hemodynamics of arterial stenoses at elevated flow rates.
abstract: This study is concerned with the pressure drop that develops across an arterial stenosis, with particular emphasis on the effect of the stenosis at high blood flow rates induced by a locally administered vasodilator drug. Stenoses, ranging in severity from 55.7% to 91.0% reduction in lumen area were artificially induced in the femoral and carotid arteries of large mongrel dogs. Instantaneous flow rates and pressure drops were measured over a wide range of flow conditions. Mean velocities varied from 3.9 to 88.8 cm/sec. Experimental data support the applicability of a relatively simple equation for predicting the pressure drop over this wide range of velocities and stenosis geometries. Results show that blood flow through a particular artery can increase by a large factor, in the range of 4-5, under conditions of vasodilation with a corresponding large decrease in pressure distal to the stenosis. The pressure drop increases in a nonlinear manner with velocity and thereby accentuates the importance of the stenosis at elevated flow rates. We suggest that a critical stenosis be defined in terms of its effect on maximal flow rather than resting flow.
mesh_terms: D000109:Acetylcholine / Q000008:administration & dosage; D000818:Animals; D001157:Arterial Occlusive Diseases / Q000503:physiopathology*; D001794:Blood Pressure / Q000187:drug effects; D001809:Blood Viscosity; D002339:Carotid Arteries / Q000503:physiopathology; D004285:Dogs; D005263:Femoral Artery / Q000503:physiopathology; D006439:Hemodynamics / Q000187:drug effects; D012212:Rheology; D014655:Vascular Resistance / Q000187:drug effects
chemical_list: D000109:Acetylcholine