Advances in electrical assist devices

Marked improvements were realized in the development of electrically driven left ventricular assist systems. A volume reduction of 46%, a system weight reduction of 63%, and a factor of 2 improvement in overall efficiency (29%) were realized. The system, operating at a pressure of 120 mm Hg with a flow rate of approximately 7 L, requires only 7.5 W of input power. In addition, a unique brushless commutator was designed to replace standard brushes, thus increasing system life. A new polyurethane was synthesized for utilization in the TMS. This material has demonstrated high flex life in addition to being biocompatible. Further improvements in system weight and size, as well as efficiency, will be realized when flat plate pumps are mated to electric drivers.