Hydraulic driving unit and control system for artificial hearts

Abstract

A driving unit for artificial ventricles was constructed in which the power transmission is hydraulic. This avoids the danger of an air embolism, which is characteristic of pneumatic drives in the case of membrane rupture. An electromagnet as a power source drives a rolling membrane pump to move the transmission fluid to the artificial ventricle. This incompressible connection allows direct control of membrane motion and pumped blood volume simply by measuring the armature stroke. The volume-controlled mode is characterized by automatic self-regulation according to Starling's law and self-synchronization when the drive is used as a left (or right) ventricular assist device. Several measures were taken to increase the operational safety. The hemodynamic efficiency of the drive was tested in a number of in vivo experiments. The long-term stability was proven in a 12-month durability test.