The Impact of Rotational Speed and Descending Aortic Flow on Hemodynamics of a Modular Intra‐Aortic Entrainment Pump: A Numerical Study

The purpose of this study was to investigate the impact of rotational speed and descending aortic flow on hemodynamics of a modular intra-aortic entrainment pump. A modular intra-aortic entrainment pump was placed in the descending aorta, and the hemodynamics of the intra-aortic entrainment pump were investigated by computational fluid dynamics methods in relation to rotational speed and descending aortic flow. This study shows that the modular intra-aortic entrainment pump can generate more cumulative flow at lower speeds. When cardiac function is limited and the rotational speed is too high, a portion of the blood that has just been pumped is reabsorbed into the blood pump, which may cause the cumulative flow through the pump to be greater than the flow through the descending aorta. There is a strong linear relationship between cumulative flow through the modular intra-aortic entrainment pump and rotational speed, but it is not sensitive to descending aortic flow. It provides a new direction for estimating pump flow rates for this type of device. It was also found that a high rotational speed leads to an increase in turbulent kinetic energy, shear stress volume fraction, and hemolysis index within the flow field near the modular intra-aortic entrainment pump, while a decrease in descending aortic flow results in a significant increase in hemolysis index. This shows that the rotational speed of the modular intra-aortic entrainment pump needs to be adjusted according to the degree of heart failure to avoid secondary blood damage and increased ventricular afterload.