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IntroductionPrimary pulmonary vein stenosis (PVS) is a rare congenital heart disease that proves to be a clinical challenge due to the rapidly progressive disease course and high rates of treatment complications. PVS intervention is frequently faced with in-stent restenosis and persistent disease progression despite initial venous recanalization with balloon angioplasty or stenting. Alterations in wall shear stress (WSS) have been previously associated with neointimal hyperplasia and venous stenosis underlying PVS progression. Thus, the development of patient-specific three-dimensional (3D)in vitromodels is needed to further investigate the biomechanical outcomes of endovascular and surgical interventions. MethodsIn this study, deidentified computed tomography images from three patients were segmented to generate perfusable phantom models of pulmonary veins before and after catheterization. These 3D reconstructions were 3D printed using a clear resin ink and used in a benchtop experimental setup. Computational fluid dynamic (CFD) analysis was performed on modelsin silicoutilizing Doppler echocardiography data to represent thein vivoflow conditions at the inlets. Particle image velocimetry was conducted using the benchtop perfusion setup to analyze WSS and velocity profiles and the results were compared with those predicted by the CFD model. ResultsOur findings indicated areas of undesirable alterations in WSS before and after catheterization, in comparison with the published baseline levels in the healthyin vivotissues that may lead to regional disease progression. DiscussionThe established patient-specific 3Din vitromodels and the developedin vitro–in silicoplatform demonstrate great promise to refine interventional approaches and mitigate complications in treating patients with primary PVS.
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This content will become publicly available on April 30, 2026
Comparative Computational Fluid Dynamics Analysis of Pulmonary Airway Flow and Surgical Outcomes for a Patient with Tracheal Stenosis
Abstract Tracheal stenosis, a severe airway narrowing, poses significant challenges in respiratory function and often necessitates surgical intervention to restore proper airflow. This study aims to demonstrate how computational fluid dynamics (CFD) can provide a non-invasive, efficient, and highly individualized approach to assist surgeons in modeling and planning various surgical strategies for treatment. The CFD-based approach in this study provides significant advantages, including reduced time and cost, and the ability to analyze complex pulmonary airflow characteristics that are difficult to investigate using in vitro and in vivo studies. This research compares three tracheal geometries: a diseased airway with tracheal stenosis and two post-surgical configurations from different surgical plans. Simulations were conducted under four inhalation flow rates, i.e., rest (6 L/min), normal (30 L/min), moderate (60 L/min), and intensive exercise (120 L/min), to evaluate the impact of surgical outcomes on pulmonary airflow dynamics. The upper airway, modeled with a mouth inlet diameter of 20 mm, exhibited average velocities of 0.32, 1.59, 3.18, and 6.37 m/s, corresponding to the respective flow rates. The laminar model was used for the rest flow rate, while the shear stress transport (SST) k-ω model was applied to simulate turbulence with higher inhalation flow rates. The results revealed substantial improvements in flow parameters following surgery. The stenotic geometry exhibited extreme resistance, with pressure drops increasing from 1.96 Pa at rest to 318.9 Pa under intensive flow, and high wall shear stress (WSS) values peaking at 330.8 Pa. Surgical Plan 1 reduced pressure drops by up to 47% and WSS by 97%, while Surgical Plan 2 achieved even greater reductions, with pressure drops lowered by 45% and WSS reduced to 2.54 Pa under high flow rates. Localized flow disturbances, such as uneven airflow distribution among lung lobes, were also alleviated post-surgery. In the diseased airway, the right lower lobe received up to 40% of the total flow, causing severe imbalances. Surgical Plan 2 achieved the most uniform distribution, with all lobes receiving 13%-29% of airflow across all flow rates, ensuring effective oxygenation and minimizing risks of overdistension or under-perfusion. These findings suggest that the CFD-based approach employed in this study can effectively model surgical outcomes, providing surgeons with a fast, detailed, and non-invasive tool for tailoring procedures to individual patient needs.
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- Award ID(s):
- 2120688
- PAR ID:
- 10611588
- Publisher / Repository:
- American Society of Mechanical Engineers
- Date Published:
- ISBN:
- 978-0-7918-8873-5
- Format(s):
- Medium: X
- Location:
- Minneapolis, MN, USA
- Sponsoring Org:
- National Science Foundation
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