Supervised Adaptive Fuzzy Control of LVAD with Pulsatility Ratio Modulation

Left ventricular assistive devices (LVAD) have been used for patients who experience congestive heart failures and are waiting for heart transplantation. These devices can help patients to resume their daily life/work until a suitable donor is found. LVAD mainly consists of a rotary pump that is directly attached from the left ventricle to the aorta using two cannulas. To meet patients’ needs, a control algorithm should be implemented to adjust the pump speed in different physiological conditions such as exercising, resting, etc. However, the accurate control of LVADs is still a challenging problem due to the unavailability of hemodynamic variables measurements, the requirement for suction avoidance, and the varying nature of the heart in different scenarios. In this study, a supervised adaptive fuzzy control strategy with pulsatility ratio modulation has been implemented to not only provide enough perfusion for the circulatory system but also to prevent suction phenomena. It has been shown that the proposed adaptive fuzzy control scheme presents a faster response compared to the previously developed fuzzy controller for LVAD and at the same time shows a faster response to push the system out of the suction area if happens. Most importantly, it has been demonstrated that the supervised adaptive fuzzy controller could help the system to stay away from the suction bound compared to the conventional methods.