Kinematic characterization of valvular opening.

The evaluation of the valvular opening due to a pulse flow, as is the case of cardiac valves, requires the knowledge of the leaflets material properties and the coupled solution of the fluid and solid equations. This approach is not commonly feasible. A different approach is introduced here to describe the opening behavior of valvular leaflets by a functional kinematic relationship. The asymptotic analysis, in the limit of leaflet opening without vortex shedding, is presented for a two-dimensional rigid leaflet model under the irrotational scheme. The approach is then verified by numerical solution of the Navier-Stokes equation in asymptotic and nonasymptotic conditions.