Shunt Flow of the Total Artificial Heart with a Single Maglev Motor

A magenetically levitated total artificial heart (IB-Heart) has been developd. It has a single maglev motor at the center and has two centrifugal pumps for the left and the right ventricles on the both side of motor. A left impeller and a right imppeller are connected with a shaft through the center of the maglev motor, so those impellers rotate with the same speed. It is important to balance the left and right flow rate, when using a total artificial heart. The IB-Heart has a shunt. In this study, in order to investigate the relationships between a shunt flow and a condition of driving the IB-Heart, the pressures at inlet and outlet ports of both side pumps, and flow rates in the shunt were measured with a same rotational speed. When the pessure difference between left outlet and right inlet is increased by 10 mmHg, the flow rate at the shunt is increased by 0.15 L/min. Also the pressure distribution at this time on the back of the both side impellers was obtained by CFD analysis. The result of this analysis indicates that the pressure distribution is affected by balance halls in the right impeller, so further investigation of the influence of balance hall is needed.