title: Comparison of novel physiological load-adaptive control strategies for ventricular assist devices.
abstract: Terminal heart failure (HF) is the most prevalent cause of death in the Western world and the implantation of a left ventricular assist device (LVAD) has become the gold standard therapy today. Most of the actually implanted devices are driven at a constant speed (CS) regardless of the patient's physiological demand. A new physiological controller [power ratio (PR) controller], which keeps a constant ratio between LVAD power and left ventricular power, a previous concept [preload responsive speed (PRS) controller], which adds a variable LVAD power to reach a defined stroke work, and a CS controller were compared with an unimpaired ventricle in a full heart computer simulation model. The effects of changes in preload, afterload and left ventricular contractility are displayed by global hemodynamics and ventricular pressure-volume loops. Both physiological controllers demonstrated the desired load dependency, whereas the PR controller exceeded the PRS controller in response to an increased load and contractility. Response was inferior when preload or contractility was decreased. Thus, the PR controller might lead to an increased exercise tolerance of the patient. Additional studies are required to evaluate the controllers in vivo.
authors.affiliation: Department of Anaesthesiology, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074 Aachen.
authors.forename: Moriz
authors.initials: M
authors.lastname: Habigt
authors.affiliation: Institute of Automatic Control, RWTH Aachen University, 52072 Aachen.
authors.forename: Maike
authors.initials: M
authors.lastname: Ketelhut
authors.affiliation: Institute of Automatic Control, RWTH Aachen University, 52072 Aachen.
authors.forename: Jonas
authors.identifier: http://orcid.org/0000-0003-4476-8727
authors.initials: J
authors.lastname: Gesenhues
authors.affiliation: Institute of Automatic Control, RWTH Aachen University, 52072 Aachen.
authors.forename: Frank
authors.initials: F
authors.lastname: Schrödel
authors.affiliation: Department of Anaesthesiology, University Hospital RWTH Aachen, 52074 Aachen.
authors.forename: Marc
authors.initials: M
authors.lastname: Hein
authors.affiliation: Department of Anaesthesiology, University Hospital RWTH Aachen, 52074 Aachen.
authors.forename: Mare
authors.initials: M
authors.lastname: Mechelinck
authors.affiliation: Institute of Applied Medical Engineering, RWTH Aachen University, 52074 Aachen.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmitz-Rode
authors.affiliation: Institute of Automatic Control, RWTH Aachen University, 52072 Aachen.
authors.forename: Dirk
authors.initials: D
authors.lastname: Abel
authors.affiliation: Department of Anaesthesiology, University Hospital RWTH Aachen, 52074 Aachen.
authors.forename: Rolf
authors.initials: R
authors.lastname: Rossaint
mesh_terms: D003198:Computer Simulation; D025461:Feedback, Physiological; D006333:Heart Failure / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy*; D006353:Heart-Assist Devices; D006801:Humans; D008955:Models, Cardiovascular; D013813:Therapy, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D016896:Treatment Outcome
keywords: cardiovascular simulation model; physiological controller; preload recruitable stroke work; ventricular assist device; ventricular unloading