Impact of extra-anatomical bypass on coarctation fluid dynamics using patient-specific lumped parameter and Lattice Boltzmann modeling

Abstract

Accurate hemodynamic analysis is not only crucial for successful diagnosis of coarctation of the aorta (COA), but intervention decisions also rely on the hemodynamics assessment in both pre and post intervention states to minimize patient risks. Despite ongoing advances in surgical techniques for COA treatments, the impacts of extra-anatomic bypass grafting, a surgical technique to treat COA, on the aorta are not always benign. Our objective was to investigate the impact of bypass grafting on aortic hemodynamics. We investigated the impact of bypass grafting on aortic hemodynamics using a patient-specific computational-mechanics framework in three patients with COA who underwent bypass grafting. Our results describe that bypass grafting improved some hemodynamic metrics while worsened the others: (1) Doppler pressure gradient improved (decreased) in all patients; (2) Bypass graft did not reduce the flow rate substantially through the COA; (3) Systemic arterial compliance increased in patients #1 and 3 and didn’t change (improve) in patient 3; (4) Hypertension got worse in all patients; (5) The flow velocity magnitude improved (reduced) in patient 2 and 3 but did not improve significantly in patient 1; (6) There were elevated velocity magnitude, persistence of vortical flow structure, elevated turbulence characteristics, and elevated wall shear stress at the bypass graft junctions in all patients. We concluded that bypass graft may lead to pseudoaneurysm formation and potential aortic rupture as well as intimal hyperplasia due to the persistent abnormal and irregular aortic hemodynamics in some patients. Moreover, post-intervention, exposures of endothelial cells to high shear stress may lead to arterial remodeling, aneurysm, and rupture.

Stress Load and Ascending Aortic Aneurysms: An Observational, Longitudinal, Single-Center Study Using Computational Fluid Dynamics

“…In contrast, in the present study, we found that elevated pressure (≥100 Pa) correlated independently with aneurysm growth. As discussed by Sadeghi et al [ 6 ], although the WSS has been recognized to influence the progression of vascular diseases, including AAoA progression and rupture, it is not yet well established in clinical practice as a tool for understanding prognosis or planning interventions.…”

“…Surgery is planned based on the diameter of the ascending aorta, obtained by imaging, under periodic monitoring [ 1 , 2 , 3 ]. In this context, in recent years, specific geometry studies have emerged to assess the risk of various cardiovascular diseases [ 4 , 5 , 6 ]. However, comparisons of aortic diameter are hampered by the asymmetry of this artery [ 7 ], and it has been shown to be an insufficient risk predictor in patients with AAoA [ 8 ].…”

Repaired Tetralogy of Fallot Pressure Assessment: Insights from 4D-Flow Pressure Mapping

“…In our study, we considered only the experimental component as a validation and comparison of pressure methods. Furthermore, several studies proposed the integration of computational fluid dynamics (CFD) with 4D-flow MRI to overcome the spatial and temporal limitations of 4D-flow MRI [40,65,66]. In particular, finite element methods can be used to discretize the in vivo 4D-flow velocity field and estimate the pressure maps more accurately [10,67].…”

Impact of TAVR on coronary artery hemodynamics using clinical measurements and image‐based patient‐specific in silico modeling

“…The previously created model, C3V-LPM, was validated against clinical catheterization data in forty-nine AS patients with a substantial inter- and intra-patient variability with a wide range of disease 41 . In addition, some of the sub-models of the patient-specific LPM algorithm have been used and validated previously 30 , 31 , 42 – 52 , with validation against in vivo cardiac catheterization 53 , 54 in patients with vascular diseases, in vivo MRI data 55 in patients with AS, and in vivo MRI data 56 – 58 in patients with coarctation and mixed valvular diseases.…”