Control system modification of an electromechanical pulsatile total artificial heart

A reliable control system is one of the most important characteristics of the electromechanical pulsatile total artificial heart (TAH). Obtaining an error-free procedure is essential for a successful in vivo implantation. To avoid any malfunction of the electrical control system, a modification of the previously designed controller was made to ensure stable pumping without the Hall effect sensor missensing. The installation position of the Hall effect sensor was changed from the top of the housing to the central piece with small magnets being installed in the stabilizer rods. The usage of the Hall effect sensor was chosen as an electrical switch. An in vitro one month running test of the TAH demonstrated adequate hydrodynamic performance with a completely error-free pumping characteristic. The total efficiency of the TAH was 12.6 +/- 1.4% at an 8 L/min outflow and 10.7 +/- 1.0% at a 6 L/min outflow condition.