Print Email Facebook Twitter Aortic valve neocuspidization and bioprosthetic valves Title Aortic valve neocuspidization and bioprosthetic valves: Evaluating turbulence haemodynamics Author Manchester, Emily Louise (Imperial College London; The University of Manchester) Pirola, S. (TU Delft Medical Instruments & Bio-Inspired Technology; Imperial College London) Pirola, Sergio (IRCCS Centro Cardiologico Monzino) Mastroiacovo, Giorgio (IRCCS Centro Cardiologico Monzino) Polvani, Gianluca (IRCCS Centro Cardiologico Monzino; University of Milan) Pontone, Gianluca (University of Milan; IRCCS Centro Cardiologico Monzino) Xu, Xiao Yun (Imperial College London) Date 2024 Abstract Aortic valve disease is often treated with bioprosthetic valves. An alternative treatment is aortic valve neocuspidization which is a relatively new reparative procedure whereby the three aortic cusps are replaced with patient pericardium or bovine tissues. Recent research indicates that aortic blood flow is disturbed, and turbulence effects have yet to be evaluated in either bioprosthetic or aortic valve neocuspidization valve types in patient-specific settings. The aim of this study is to better understand turbulence production in the aorta and evaluate its effects on laminar and turbulent wall shear stress. Four patients with aortic valve disease were treated with either bioprosthetic valves (n=2) or aortic valve neocuspidization valvular repair (n=2). Aortic geometries were segmented from magnetic resonance images (MRI), and 4D flow MRI was used to derive physiological inlet and outlet boundary conditions. Pulsatile large-eddy simulations were performed to capture the full range of laminar, transitional and turbulence characteristics in the aorta. Turbulence was produced in all aortas with highest levels occurring during systolic deceleration. In the ascending aorta, turbulence production is attributed to a combination of valvular skew, valvular eccentricity, and ascending aortic dilation. In the proximal descending thoracic aorta, turbulence production is dependent on the type of arch-descending aorta connection (e.g., a narrowing or sharp bend) which induces flow separation. Laminar and turbulent wall shear stresses are of similar magnitude throughout late systolic deceleration and diastole, although turbulent wall shear stress magnitudes exceed laminar wall shear stresses between 27.3% and 61.1% of the cardiac cycle. This emphasises the significance of including turbulent wall shear stress to improve our comprehension of progressive arterial wall diseases. The findings of this study recommend that aortic valve treatments should prioritise minimising valvular eccentricity and skew in order to mitigate turbulence generation. Subject Aortic valve neocuspidizationAortic valve replacementBioprosthesisBlood flowComputational fluid dynamicsHaemodynamicsLarge-eddy simulationOzaki procedureTurbulenceWall shear stress To reference this document use: http://resolver.tudelft.nl/uuid:678c1b29-f517-4918-9980-75cbb9677548 DOI https://doi.org/10.1016/j.compbiomed.2024.108123 ISSN 0010-4825 Source Computers in Biology and Medicine, 171 Part of collection Institutional Repository Document type journal article Rights © 2024 Emily Louise Manchester, S. Pirola, Sergio Pirola, Giorgio Mastroiacovo, Gianluca Polvani, Gianluca Pontone, Xiao Yun Xu Files PDF 1-s2.0-S0010482524002075-main.pdf 3.12 MB Close viewer /islandora/object/uuid:678c1b29-f517-4918-9980-75cbb9677548/datastream/OBJ/view