title: A modular computational circulatory model applicable to VAD testing and training.
abstract: Aim of this work was to develop a modular computational model able to interact with ventricular assist devices (VAD) for research and educational applications. The lumped parameter model consists of five functional modules (left and right ventricles, systemic, pulmonary, and coronary circulation) that are easily replaceable if necessary. The possibility of interacting with VADs is achieved via interfaces acting as impedance transformers. This last feature was tested using an electrical VAD model. Tests were aimed at demonstrating the possibilities and verifying the behavior of interfaces when testing VADs connected in different ways to the circulatory system. For these reasons, experiments were performed in a purely numerical mode, simulating a caval occlusion, and with the model interfaced to an external left-VAD (LVAD) in two different ways: with atrioaortic and ventriculoaortic connection. The caval occlusion caused the leftward shift of the LV p-v loop, along with the drop in arterial and ventricular pressures. A narrower LV p-v loop and cardiac output and aortic pressure rise were the main effects of atrioaortic assistance. A wider LV p-v loop and a ventricular average volume drop were the main effects of ventricular-aortic assistance. Results coincided with clinical and experimental data attainable in the literature. The model will be a component of a hydronumerical model designed to be connected to different types of VADs. It will be completed with autonomic features, including the baroreflex and a more detailed coronary circulation model.
authors.affiliation: Institute of Clinical Physiology, Section of Rome, CNR, Via San Martino della Battaglia 44, 00185 Rome, Italy. gfr.ferrari@ifc.cnr.it
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Ferrari
authors.forename: Maciej
authors.initials: M
authors.lastname: Kozarski
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Zieliński
authors.forename: Libera
authors.initials: L
authors.lastname: Fresiello
authors.forename: Arianna
authors.initials: A
authors.lastname: Di Molfetta
authors.forename: Krystyna
authors.initials: K
authors.lastname: Górczyńska
authors.forename: Krzysztof J
authors.initials: KJ
authors.lastname: Pałko
authors.forename: Marek
authors.initials: M
authors.lastname: Darowski
mesh_terms: D002302:Cardiac Output / Q000502:physiology*; D003198:Computer Simulation; D003326:Coronary Circulation / Q000502:physiology*; D006321:Heart / Q000502:physiology*; D006353:Heart-Assist Devices; D006801:Humans; D008955:Models, Cardiovascular