Dynamic modeling of variable speed left ventricular assist devices coupled to the cardiovascular system.

Background: Most of the modeling of the Left Ventricular Assist Devices (LVADs) coupled with the cardiovascular system is based on the assumption of constant rotational speed. Compared with the traditional inertial model, the validated hysteresis model can take into account the unsteady characteristics of LVADs, but it fails to work under the condition of variable speed modulation.

Method: This study takes into consideration the impact of speed variations on the unsteady hysteresis effects.