Hemodynamic analysis of outflow grafting positions of a ventricular assist device using closed-loop multiscale CFD simulations: Preliminary results.
Subclavian arteries are a possible alternate location for left ventricular assist device (LVAD) outflow grafts due to easier surgical access and application in high risk patients. As vascular blood flow mechanics strongly influence the clinical outcome, insights into the hemodynamics during LVAD support can be used to evaluate different grafting locations. In this study, the feasibility of left and right subclavian artery (SA) grafting was investigated for the HeartWare HVAD with a numerical multiscale model. A 3-D CFD model of the aortic arch was coupled to a lumped parameter model of the cardiovascular system under LVAD support. Grafts in the left and right SA were placed at three different anastomoses angles (90°, 60° and 30°). Additionally, standard grafting of the ascending and descending aorta was modelled. Full support LVAD (5l/min) and partial support LVAD (3l/min) in co-pulsation and counter-pulsation mode were analysed. The grafting positions were investigated regarding coronary and cerebral perfusion. Furthermore, the influence of the anastomosis angle on wall shear stress (WSS) was evaluated. Grafting of left or right subclavian arteries has similar hemodynamic performance in comparison to standard cannula positions. Angularity change of the graft anastomosis from 90° to 30° slightly increases the coronary and cerebral blood flow by 6-9% while significantly reduces the WSS by 35%. Cannulation of the SA is a feasible anastomosis location for the HVAD in the investigated vessel geometry.
Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany; Enmodes GmbH, Aachen, Germany. Electronic address: neidlin@ame.rwth-aachen.de.
Michael
M
Neidlin
Laboratory of Biological Structure Mechanics, Department of Chemistry, Materials and Chemical Engineering ''Giulio Natta'', Politecnico di Milano, Milano, Italy.
Chiara
C
Corsini
Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany; Enmodes GmbH, Aachen, Germany.
Simon J
SJ
Sonntag
Department of Cardiac Surgery, Schüchtermann Clinic Bad Rothenfelde, Germany.
Sebastian
S
Schulte-Eistrup
Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany.
Thomas
T
Schmitz-Rode
Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany.
Ulrich
U
Steinseifer
Laboratory of Biological Structure Mechanics, Department of Chemistry, Materials and Chemical Engineering ''Giulio Natta'', Politecnico di Milano, Milano, Italy.
Giancarlo
G
Pennati
Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany; Enmodes GmbH, Aachen, Germany.
Tim A S
TAS
Kaufmann
D001011:Aorta / Q000502:physiology; D001013:Aorta, Thoracic / Q000502:physiology; D002404:Catheterization; D003198:Computer Simulation; D006353:Heart-Assist Devices; D006439:Hemodynamics; D057446:Hydrodynamics; D008955:Models, Cardiovascular; D013348:Subclavian Artery / Q000502:physiology
Computational fluid dynamics; Lumped parameter modelling; Multiscale simulations; Outflow grafting; VAD hemodynamics