Computational Investigation of Magneto-Hydrodynamic Assist Device for Actively Powered Fontan Circulations
Around 8% of all newborns with a Congenital Heart Defect (CHD) have a single ventricle (SV) anatomy. Affected children must undergo three palliative surgeries to establish viable SV physiology. The Fontan circulation is the result of the third surgery. Despite successful implementation over the years, the Fontan circulation is prone to failure with survival rates of less than 50%. One of the failure modes is increased inferior vena cava (IVC) pressure. We propose a novel solution by implementing a magneto-hydrodynamic assist device (MhAD) to increase pulmonary blood flow while decreasing the IVC pressure. This design is conceptually attractive because of the
absence of moving parts potentially obtrusive to the bloodstream; hence it may reduce incidences of morbidity and may serve as a true percutaneous implant. Following ongoing analysis, we report preliminary results using a patient-generic geometry implementing multi-physics modeling under incompressible steady-flow conditions. A computational fluid dynamics (CFD) model has been setup by placing the MhAD on the inferior vena cava (IVC) with clinically relevant mass flow rates and static pressures as inlet and outlet boundary conditions. Our calculations show that by varying the applied magnetic and electric field, the MhAD generates enough Lorentz
force to create an appreciable increase in the blood flow across the IVC. These findings suggest that model parameters such as field strength, voltage, hemodynamic properties, and geometry of the device will affect the efficacy of the MhAD, hence requiring tailored optimization.