Applications of modeling and identification in ventricular assist device development

Left ventricular assist devices (LVAD) are blood pumps used to boost cardiac output for patients who suffer from heart failure. They can be used as a therapy to allow the patient´s heart to recover, as a temporary device to support patient while waiting for heart transplant, and as a long-term alternative to transplantation. The new generation of LVADs employs the turbo-dynamic method to pump blood by continuously rotating the impeller in the device. These devices are smaller in size with better efficiency and no valve in comparison with their pulsatile predecessors. However, the new devices also bring new challenges in terms of safety operation of the devices. This paper provides a review of applications that use modeling and identification techniques in rotary LVAD development. The flow estimation algorithms and hydrodynamic bearing monitoring system developed for the AB-180 LVAD (CardiacAssist Inc., Pittsburgh, PA, USA) are presented as the feasibility proof.