P10: CFD Simulation Of Thrombosis In A Catheter Pump Inside The Left Ventricle

Abstract

Study: Catheter pumps are small axial flow assist devices indicated for temporary use for a variety of indications. Uniquely positioned within the circulation, the pump impeller and motor are situated in the ascending aorta, and blood is pumped from the left ventricle (LV) via a long angled inlet cannula. The interplay of pulsatile LV blood dynamics with hemocompatibility performance of a catheter pump is not well characterized. The purpose of this study is to conduct computational fluid dynamics (CFD) simulation that includes multifactorial and synergistic models of blood damage to a catheter pump within a virtual in-vivo environment to analyze its hemodynamics. Methods: A generic catheter pump whose shape is inspired by the Impella 5.0 is situated within a static geometry consisting of a semi-realistic LV and aorta. We apply bloodDamageFoam, an OpenFOAM-based CFD code, to predict the hemodynamic flow and blood damage generated by the pump operating at 20 kRPM. The thrombosis model includes seven biochemical and biophysical agonists and accounts for the effects of high shear stress induced activation of von Willebrand factor. Results: CFD predicted 4.43 LPM blood flow rate from the LV delivered into the aorta. Moderate levels of hemolysis were predicted. The thrombosis model showed moderate degrees of platelet deposition on the cage of the inlet cannula and within the catheter pump chamber. Because the LV in this simulation was not beating, unrealistically large regions of flow stagnation and high platelet activation were observed in the LV. To address this, realistic pulsatility of a dilated LV is currently being modeled. Our latest progress will be presented at the meeting.