Premium
Physiological Control of Dual Rotary Pumps as a Biventricular Assist Device Using a Master/Slave Approach
Author(s) -
Stevens Michael C.,
Wilson Stephen,
Bradley Andrew,
Fraser John,
Timms Daniel
Publication year - 2014
Publication title -
artificial organs
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.684
H-Index - 76
eISSN - 1525-1594
pISSN - 0160-564X
DOI - 10.1111/aor.12303
Subject(s) - suction , controller (irrigation) , starling , ventricular assist device , control theory (sociology) , control system , medicine , cardiology , heart failure , computer science , control (management) , engineering , mechanical engineering , electrical engineering , artificial intelligence , agronomy , biology
Dual rotary left ventricular assist devices ( LVAD s) can provide biventricular mechanical support during heart failure. Coordination of left and right pump speeds is critical not only to avoid ventricular suction and to match cardiac output with demand, but also to ensure balanced systemic and pulmonary circulatory volumes. Physiological control systems for dual LVAD s must meet these objectives across a variety of clinical scenarios by automatically adjusting left and right pump speeds to avoid catastrophic physiological consequences. In this study we evaluate a novel master/slave physiological control system for dual LVAD s. The master controller is a Starling‐like controller, which sets flow rate as a function of end‐diastolic ventricular pressure ( EDP ). The slave controller then maintains a linear relationship between right and left EDP s. Both left/right and right/left master/slave combinations were evaluated by subjecting them to four clinical scenarios (rest, postural change, Valsalva maneuver, and exercise) simulated in a mock circulation loop. The controller's performance was compared to constant‐rotational‐speed control and two other dual LVAD control systems: dual constant inlet pressure and dual Frank–Starling control. The results showed that the master/slave physiological control system produced fewer suction events than constant‐speed control (6 vs. 62 over a 7‐min period). Left/right master/slave control had lower risk of pulmonary congestion than the other control systems, as indicated by lower maximum EDP s (15.1 vs. 25.2–28.4 mm Hg). During exercise, master/slave control increased total flow from 5.2 to 10.1 L/min, primarily due to an increase of left and right pump speed. Use of the left pump as the master resulted in fewer suction events and lower EDP s than when the right pump was master. Based on these results, master/slave control using the left pump as the master automatically adjusts pump speed to avoid suction and increases pump flow during exercise without causing pulmonary venous congestion.