Pressure-flow dynamics in the right ventricular outflow-tract were analyzed during sequential increases in cardiac sympathetic nerve activity in dogs anesthetized with chloralose. The aim of this study was to provide a precise definition of the extrinsic nervous control of pressure and flow in the right ventricle. The left stellate ganglion was stimulated at 1, 2, 5, 10, 15 and 20 cps. At each stimulus frequency, systolic pressure differences from the sinus (inflow region) to the conus (outflow region) of the right ventricle were determined as a function of pressure measured parallel (lateral) and perpendicular (impact) to the flow stream in the outflow-tract. These measurements allowed for the assessment of the magnitude of kinetic pressure and permitted an analysis of the influence of the kinetic component upon the formation of outflow-tract pressure differences. Impact pressure was assumed to be proportional to momentum (MV) plus static or lateral pressure. Nerve stimulation caused peak sinus pressure to increase to a greater extent than either conus impact or later pressure with the consequent formation of a sinus-conus pressure difference. The pressure difference wave-form was
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