Feedback Control of an LVAD Supporting a Failing Cardiovascular System Regulated by the Baroreflex

The baroreflex is an internal feedback mechanism that stabilizes the blood pressure in the circulatory system. Its function in patients with congestive heart failure is preserved fairly well. When these patients are implanted with a left ventricular assist device (LVAD), the baroreflex plays an important role in interacting with the controller that regulates the pump speed. In this paper, we consider a combined model of the cardiovascular system, the baroreflex mechanism, and an LVAD. We present results that will describe the interaction mechanisms between these three subsystems. We then propose a feedback controller for the LVAD which automatically adjust its speed based on the systemic vascular resistance (SVR) and heart rate (HR) under varying patient conditions. Simulation results show that the combined model is capable of reproducing human responses to exercise and the proposed controller is able to respond to change in physiological state of patients with heart failure