Key result
In a computational fluid-structure interaction model, increasing matrix stiffness up to 200 kPa increased transvalvular pressure up to 20 mmHg and decreased effective orifice area to 2.10 cm2.
Computational modeling demonstrates that both matrix stiffness and fiber orientation significantly affect the effective orifice area and transvalvular pressure gradient of prosthetic trileaflet heart valves, suggesting these parameters can be tailored to optimize valve dynamics.
Stiffness may impair valve hemodynamics in models; leaves open its role in clinical aortic stenosis.
Biological valves are employed for aortic valve substitution since a long time but there is a growing effort toward the development of new engineered tissues, in which the complex mechanical response of native leaflets is replicated using composite materials consisting of a soft matrix with embedded reinforcing fibers. The main goal of the present study is to investigate the influence that variations on fiber orientation and matrix stiffness may have on valve dynamics. To this aim, a fluid–structure interaction (FSI) model of a trileaflet valve was implemented in which the opening phase was simulated and leaflet matrix stiffness and fiber orientation were varied in the framework of an anisotropic hyperelastic strain energy function. Results show that both parameters may affect significantly transvalvular pressure gradient and effective orifice area (EOA). For the opening phase of the valve examined, less favorable flow conditions were found when preferred fiber orientation is circumferential, due to lower maximum EOA achievable. Such configuration in combination with stiffer matrix may result in significant degradation of valve performances. Overall fiber orientation can potentially be taylored to optimize valve dynamics, provided also structural aspects that may be prominent in the closure phase, are considered.
No takes yet. Share an insight, caveat, or question.
Andrea Avanzini (2017) studied Prosthetic heart valve dynamics. Variations in leaflet matrix stiffness and fiber orientation vs. Reference configuration (c10 = 20.1 kPa, β = 29.8°) was evaluated on Transvalvular pressure gradient (DPave) and effective orifice area (EOA). In a computational fluid-structure interaction model, increasing matrix stiffness up to 200 kPa increased transvalvular pressure up to 20 mmHg and decreased effective orifice area to 2.10 cm2.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: