RT Journal Article
SR Electronic
T1 Fluid-structure interaction analysis of eccentricity and leaflet rigidity on thrombosis biomarkers in bioprosthetic aortic valve replacements
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2022.01.06.475272
DO 10.1101/2022.01.06.475272
A1 David Oks
A1 Mariano Vázquez
A1 Guillaume Houzeaux
A1 Constantine Butakoff
A1 Cristóbal Samaniego
YR 2022
UL http://biorxiv.org/content/early/2022/01/07/2022.01.06.475272.abstract
AB This work introduces the first 2-way fluid-structure interaction (FSI) computational model to study the effect of aortic annulus eccentricity on the performance and thrombogenic risk of cardiac bioprostheses. The model predicts that increasing eccentricities yield lower geometric orifice areas (GOAs) and higher normalized transvalvular pressure gradients (TPGs) for healthy cardiac outputs during systole, agreeing with in vitro experiments. Regions with peak values of residence time and shear rate are observed to grow with eccentricity in the sinus of Valsalva, indicating an elevated risk of thrombus formation for eccentric configurations. In addition, the computational model is used to analyze the effect of varying leaflet rigidity on both performance, thrombogenic and calcification risks with applications to tissue-engineered prostheses, observing an increase in systolic and diastolic TPGs, and decrease in systolic GOA, which translates to decreased valve performance for more rigid leaflets. An increased thrombogenic risk is detected for the most rigid valves. Peak solid stresses are also analyzed, and observed to increase with rigidity, elevating risk of valve calcification and structural failure. The immersed FSI method was implemented in a high-performance computing multi-physics simulation software, and validated against a well known FSI benchmark. The aortic valve bioprosthesis model is qualitatively contrasted against experimental data, showing good agreement in closed and open states. To the authors’ knowledge this is the first computational FSI model to study the effect of eccentricity or leaflet rigidity on thrombogenic biomarkers, providing a novel tool to aid device manufacturers and clinical practitioners.Competing Interest StatementMariano Vazquez is CTO and co-founder of private company ELEM Biotech, Constantine Butakoff is senior scientific developer at ELEM Biotech. The rest of the authors declare no potential conflict of interests.BSCBarcelona Supercomputing CenterFSIFluid-Structure InteractionGOA & EOAGeometric & Effective Orifice AreaTPGTransvalvular Pressure GradientAVRAortic Valve ReplacementMAVR, BAVR, TAVR & SAVRMechanical, Bioprosthetic, Transcatheter & Surgical Aortic Valve ReplacementsCFDComputational Fluid DynamicsCSMComputational Solid MechanicsQoIQuantity of InterestFEFinite ElementALEArbitrary Lagrangian-EulerianBCM & NBCMBoundary-Conforming & Non Boundary-Conforming MethodsLVHLeft Ventricular HypertrophyEIEccentricity IndexCOCardiac OutputVVUQVerification, Validation & Uncertainty Quantification