Experimental study of an asymmetric heart valve prototype

Clinical studies show that the fluid motion within the left ventricle can be strongly altered by the presence of standard mechanical heart valves (MHVs). It is also acknowledged that even small changes in the geometry of the valvular leaflets can induce significant changes in the intraventricular flow features. In the MHVs actually implanted, two symmetric leaflets exist: their geometry and performance diverge from those of the native ones possibly leading to serious functional complications of the heart. With the aim of designing a heart valve prosthesis akin to the native one and more suitable for the mitral valve replacement, we designed an original, home-made asymmetric MHV prototype, characterized by two unequal leaflets and an amplified central orifice. The intraventricular flow pattern that originates downstream of this prototype is experimentally investigated and compared with that corresponding to mono- and bi-leaflet standard prosthesis. Results show that the asymmetric geometry of the prototype induces both a fluid dynamics and an energetic behavior closer to that of natural valves, of basic importance for the overall functionality of the heart.