Evaluating the roles of detailed endocardial structures on right ventricular haemodynamics by means of CFD simulations

Abstract

Computational modelling plays an important role in right ventricular (RV) haemodynamic analysis. However, current approaches use smoothed ventricular anatomies. The aim of this study is to characterise RV haemodynamics including detailed endocardial structures like trabeculae, moderator band, and papillary muscles. Four paired detailed and smoothed RV endocardium models (2 male and 2 female) were reconstructed from ex vivo human hearts high-resolution magnetic resonance images. Detailed models include structures with ≥1 mm cross-sectional area. Haemodynamic characterisation was done by computational fluid dynamics simulations with steady and transient inflows, using high-performance computing. The differences between the flows in smoothed and detailed models were assessed using Q-criterion for vorticity quantification, the pressure drop between inlet and outlet, and the wall shear stress. Results demonstrated that detailed endocardial structures increase the degree of intra-ventricular pressure drop, decrease the wall shear stress, and disrupt the dominant vortex creating secondary small vortices. Increasingly turbulent blood flow was observed in the detailed RVs. Female RVs were less trabeculated and presented lower pressure drops than the males. In conclusion, neglecting endocardial structures in RV haemodynamic models may lead to inaccurate conclusions about the pressures, stresses, and blood flow behaviour in the cavity.

Moving beyond size: vorticity and energy loss are correlated with right ventricular dysfunction and exercise intolerance in repaired Tetralogy of Fallot

“…There was inconsistent timing of exercise stress test in rTOF patients, although the time interval between CMR and stress tests were still within recommended surveillance guidelines of rTOF patients [ 2 ] and is unlikely to significantly alter results based on previous longitudinal studies [ 56 , 57 ]. Most importantly, the limited spatial and temporal resolution of 4D flow prohibited detailed assessment of smaller vortical interactions formed by the collision of PR into the tricuspid vortex and the propagation of turbulent flow into the RV body and myocardium, particularly the trabeculations [ 58 ]. Thus, we did not assess hemodynamic parameters such as wall shear stress along the RV free wall, which likely has an influence on RV dilation.…”

Longer time accuracy for incompressible Navier-Stokes simulations with the EMAC formulation

“…Putting our effort into a more general context, the paper addresses the challenge of providing mathematical evidence of the widely accepted concept that a better adherence to conservation laws with discretization schemes leads to more accurate numerical solutions. Numerical tests using EMAC in, e.g., [6,7,31,22,29,10,9,23,25] already show it performs very well on a wide variety of application problems, and in many instances better than other formulations, as it is found to be less numerically dissipative; hence this section gives some analytical backing to those results.…”

Percutaneous Thrombin Injection Based on Computational Fluid Dynamics of Femoral Artery Pseudoaneurysms

“…It is widely used in engineering fields such as hydrodynamics [17,18]. Recently, CFD has also been used in the medical field for flow analysis [19][20][21][22][23][24]. We used CFD to understand the blood flow patterns in FAPs to obtain helpful information or clues for performing the PTI procedure [16].…”