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 (ΔP L) and RVAD (ΔP R) to provide left-right balance and physiologic flow. To prevent ventricular suction, LVAD and RVAD pump speed differentials (ΔRPM L, ΔRPM R) 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 ΔP L and/or ΔP R 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 ΔP L and ΔP R. 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.
From the *Department of Biomedical Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, Liaoning, China; †Department of Bioengineering, Cardiovascular Innovation Institute, University of Louisville, Louisville, KY; and ‡Department of Cardiovascular and Thoracic Surgery, Cardiovascular Innovation Institute, University of Louisville, Louisville, KY.
Submitted for consideration September 2016; accepted for publication in revised form July 2017.
Supported, in part, by NIH R15 Grant (1R15HL115556–01A1) and the University of Louisville Cardiac Implant Science Endowment.
Disclosure: The authors have no conflicts of interest to report.
Correspondence: Guruprasad A. Giridharan, Department of Bioengineering, Cardiovascular Innovation Institute, Room 407, 302 East Muhammad Ali Blvd, University of Louisville, Louisville, KY 40202. Email: email@example.com.