Fluid–structure interaction of deformable aortic prostheses with a bileaflet mechanical valve

Tullio, Marco D. de; Afferrante, L.; Demelio, G.; Pascazio, G.; Verzicco, Roberto

doi:10.1016/j.jbiomech.2011.03.036

Cited by 26 publications

(27 citation statements)

References 21 publications

(20 reference statements)

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“…A direct numerical simulation approach was utilized to solve the complex fluid-structure-interaction problem and obtain detailed information of the flow patterns. 6,8 We examined the damage experienced by different models among a few characteristic pathlines The results are in line with the behavior observed in the simple shear flow numerical experiments above, and reinforce the shortcomings of existing models in highly complex hemodynamic environments. It is also important to note that for all pathlines we considered the loading on the RBC membrane almost never produced stresses that can cause tearing, but it was in the range that mechanical loading causes the spontaneous pre-pores to evolve and create holes in the membrane that result in the loss of hemoglobin.…”

Section: Discussionsupporting

confidence: 81%

“…A direct numerical simulation approach was utilized to solve the complex fluidstructure-interaction problem and obtain detailed information of the flow patterns. The details can be found in de Tullio et al 6,8 Due to the geometry of the valve, the flow is turbulent for a large part of the pulsatile cycle, and RBCs are exposed to viscous, as well as, turbulent stresses, which however, act on different length scales: the dissipative and inertial ranges of the turbulent spectrum, respectively. At the present Reynolds number (Re = 6200) we can expect a Kolmogorov scale g~40 lm, and a dissipative range extending up to lengths of~2.1 mm (see 7 for details).…”

Section: Hemolysis In Prosthetic Heart Valvesmentioning

confidence: 99%

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A Strain-Based Model for Mechanical Hemolysis Based on a Coarse-Grained Red Blood Cell Model

et al. 2015

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Mechanical hemolysis is a major concern in the design of cardiovascular devices, such as prosthetic heart valves and ventricular assist devices. The primary cause of mechanical hemolysis is the impact of the device on the local blood flow, which exposes blood elements to non-physiologic conditions. The majority of existing hemolysis models correlate red blood cell (RBC) damage to the imposed fluid shear stress and exposure time. Only recently more realistic, strain-based models have been proposed, where the RBC's response to the imposed hydrodynamic loading is accounted for. In the present work we extend strain-based models by introducing a high-fidelity representation of RBCs, which is based on existing coarse-grained particle dynamics approach. We report a series of numerical experiments in simple shear flows of increasing complexity, to illuminate the basic differences between existing models and establish their accuracy in comparison to the high-fidelity RBC approach. We also consider a practical configuration, where the flow through an artificial heart valve is computed. Our results shed light on the strengths and weaknesses of each approach and identify the key gaps that should be addressed in the development of new models.

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Section: Discussionsupporting

confidence: 81%

Section: Hemolysis In Prosthetic Heart Valvesmentioning

confidence: 99%

A Strain-Based Model for Mechanical Hemolysis Based on a Coarse-Grained Red Blood Cell Model

et al. 2015

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“…The derived pressure gradient helps to understand the workload on the heart. In other words, the BC used is unbiased for comparing different valves than that used by other researchers (Ranga et al, 2006;De Hart et al, 2003a;De Hart et al, 2003b;Maleki, 2010;Weinberg & Mofrad, 2007;De Tullio et al, 2011).…”

Section: The Proposed Bc For Unbiased Comparison Of the Valvesmentioning

confidence: 93%

“…However, a persistent issue with the valve comparison studies is in their boundary condition (BC) used for analyzing the valve. FSI simulation on the aortic valves require either a pressure BC (De Hart et al, 2003b;Maleki, 2010;Weinberg & Mofrad, 2007) or a flow BC (De Hart et al, 2003a;De Tullio et al, 2011). A time varying pressure applied at the aortic and ventricular sections of the aortic valve together form the pressure BC.…”

Section: Introductionmentioning

confidence: 99%

“…In some cases, the pressure BC will not ensure the full opening of the valve and this leads to a bias in the study. If only the flow BC is specified, it over-constrains the analysis by explicitly specifying the blood regurgitation into the left-ventricle (refer Figure 7 in (De Hart et al, 2003a), and Figure 5(a) in (De Tullio et al, 2011)). In addition, the flow BC does not ensure the full closure of the valve after ventricular ejection until a proper quantity of valve regurgitation is specified by the BC.…”

Section: Introductionmentioning

confidence: 99%

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