Design and experimental testing of a heart assist device with pulsatile flow pump

Objective:To test the pulsatile blood pumps in a mock circulation loops,and then to prove its feasibility by animal experiments.Methods:In the mock circuit,the water and Ringer′s solution were used respectively as the circulating mediums to test the performance of the heart assist devices with pulsatile flow pumps,and to prove it by animal experiments.Results:When preload was fixed,cardiac output was gradually decreased with the increase in afterload.While afterload was kept unchanged,cardiac output was almost not affected by the increase in preload.When preload was set between 10 mmHg and 50 mmHg,and afterlood was between 60 mmHg and 110 mmHg,we observed that cardiac output was changed between 4.0L and 5.9 L.Animal experiments showed that pulsatile blood pump had an supporting role in pigs with heart failure.Conclusion:The study demonstrated that cardiac output of the pulsatile blood pump is significantly restrained by afterload while preload exerts no influence on it.Further investigation is needed to explore the significance of the difference in the load response characteristics.