Feedback Control of a Rotary Left Ventricular Assist Device Supporting a failing Cardiovascular System

A new feedback control system for a current-based model of the combined cardiovascular system and a rotary left ventricular assist device is presented. The system consists of a suction detection subsystem and a feedback controller subsystem. The suction detection subsystem is based on a Lagrangian Support Vector Machine model. In the absence of suction in the left ventricle, as indicated by the suction detection subsystem, the proposed feedback controller automatically adjusts the pump motor current in order to meet the blood flow requirement of the patient's body at different physiological states. The performance of the feedback control system has been tested to show the ability to autonomously adjust the pump current, while sustaining required cardiac output and mean arterial pressure. Simulation results show that the controller can keep cardiac output and mean arterial pressure within acceptable physiologic ranges under different conditions of the patient activities. Robustness to noise of the controller is also discussed.