Sensor-Based Physiologic Control Strategy for Biventricular Support with Rotary Blood Pumps

Abstract

Rotary biventricular assist devices (BiVAD) are becoming a clinically accepted treatment option for end-stage biventricular failure. To improve BiVAD efficacy and safety, we propose a control algorithm to achieve the clinical objectives of maintaining left-right-sided balance, restoring physiologic flows, and preventing ventricular suction. The control algorithm consists of two proportional-integral (PI) controllers for left and right ventricular assist devices (LVAD and RVAD) to maintain differential pump pressure across LVAD (ΔPL) and RVAD (ΔPR) to provide left-right balance and physiologic flow. To prevent ventricular suction, LVAD and RVAD pump speed differentials (ΔRPML, ΔRPMR) were maintained above user-defined thresholds. Efficacy and robustness of the proposed algorithm were tested in silico for axial and centrifugal flow BiVAD using 1) normal and excessive ΔPL and/or ΔPR setpoints, 2) rapid threefold increase in pulmonary vascular or vena caval resistances, 3) transient responses from exercise to rest, and 4) ventricular fibrillation. The study successfully demonstrated that the proposed BiVAD algorithm achieved the clinical objectives but required pressure sensors to continuously measure ΔPL and ΔPR. The proposed control algorithm is device independent, should not require any modifications to the pump or inflow/outflow cannulae/grafts, and may be directly applied to current rotary blood pumps for biventricular support.

An Optimal H-Infinity Controller for Left Ventricular Assist Devices Based on a Starling-like Controller: A Simulation Study

“…Most VADs available on the market, both second and third generations, operate at a set target of operating points determined by a per-patient specialist clinician. Unless VADs are to be generally accepted as a care choice for HF patients, the quality of life of implant recipients must be maximized, and a pump management technique is thought to be essential to achieve this [35,36].…”

Physiological Control Law for Rotary Blood Pumps with Full-State Feedback Method

“…Naturally, as the VAD and the controller are implanted in humans, because their lifespan depends largely on the suitability of the pump control, we must have great certainty in the robustness of the control algorithms [29,30]. Continuous flow for VADs may allow simulated pulses; however, until the date of circulatory assistance, despite tolerance to left ventricular and Pao, the continuous flow rate is traditionally of a medium constant rotation, which always decreases the pressure pulse [31,32].…”

In vitro evaluation of multi‐objective physiological control of the centrifugal blood pump

“…Most physiological controllers use sensors for decision making. Those who do not use sensors report lower accuracy, according to the literature . The mentioned strategies have been verified in numerical or computational simulations and in vitro tests.…”

“…Those who do not use sensors report lower accuracy, according to the literature. [21][22][23][24][25][26][27] The mentioned strategies have been verified in numerical or computational simulations and in vitro tests. Results have been demonstrated that they were able to generate adequate blood flow and pressure.…”