Abstract

DEL RIO PALMA, Javier  and  CERROLAZA, Miguel E. Influence of fluid dynamics and structural factors in the heart valves behavior. Rev. Fac. Ing. UCV [online]. 2013, vol.28, n.4, pp.89-100. ISSN 0798-4065.

This paper compares the influence of several factors involved in the motion of heart’s valves. Some of factors are related to fluid dynamics, like blood pressure through the valve, blood motion and the vortexes in the vicinity of the valve leaflets, while other are structurally related, like the stiffness of the valve leaflets and their roughness, which is largely associated to the friction with the blood. A heart’s valve concentrated parameter model (or 0D model) is used to assess the influence of these factors. Each factor is described as a function of the valve’s opening angle, and the final model is compared with a diode model. The valve model is embedded in an overall cardiovascular system, which is described through resistances, compliances and inductances, taking into account local effects due to flow friction, elasticity of blood vessels and blood inertia. The heart’s chambers are described through a variable elastance model. The simulation results show the curves of pressure, blood flow and volume as well as the opening angle variation of the valve leaflets. These curves are compared with the curves obtained by applying a simple model, with instantaneous opening and closing, resulting in a better matching with the medical literature. It was also found that the main factors influencing the movement of the valves are the pressure differential, the rigidity of the valve leaflets and, at a less important degree, the friction between valve leaflets and the blood.

Keywords : Heart valves; Cardiovascular system; Valvular motion; Numerical simulation; models.

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