Validation of image-based direct numerical simulations of right ventricle against 4D flow*

With recent advancements in medical imaging and high-performance computing capabilities, image-based computational modeling is becoming a powerful tool with diagnostic and predictive potential for cardiovascular disease. The high temporal and spatial resolution in direct numerical simulations (DNS) allows detailed quantification of flow patterns, especially within the right ventricle (RV), which has a more complex geometry and wall motion than the widely studied left ventricle (LV). Investigating intracardiac flow phenomena can eventually provide reliable biomarkers that can be used to monitor the evolution of postoperative morbidities and the timing of surgeries, especially in congenital heart disease (CHD). Despite these advantages, computational models may suffer from uncertainties due in part to kinematic reconstruction, boundary conditions, and geometric simplifications. Therefore, the validation of simulation results is of utmost importance. In this work, we will compare DNS of the flow inside the RV with conventional four-dimensional magnetic resonance imaging (4D flow). The comparison based on healthy control cases will include the kinematics of the RV through mass conservation, phase-averaged velocity and vorticity profiles, and volume and phase-averaged flow-related quantities such as kinetic energy and viscous energy loss.