Influence of flow design on microcirculation in conditions of undulation pump-left ventricle assist device testing

To study the microvessels in bulbar conjunctiva, we conducted an experiment in goat with a pneumatically driven left heart bypass pump, which was replaced with an undulation pump-left ventricle assist device for 9 days. Three flow patterns were tested: complete pulsatile, continuous, and percentage of pulsatile. We studied the morphology of arterioles and venules of the bulbar conjunctiva using photograph records. The setting up of continuous flow caused global vasoconstriction (significant in venules-P < 0.05). During the pumping in the pulsatile and percentage of pulsatile modes, no significant changes of microvessel morphology were observed. The findings described could point to some disturbances in the microcirculatory bed in conditions of continuous flow.