Dynamic heart valve cusp bending deformation analysis

Abstract

Proper hemodynamics is a major issue in research of heart valve bio-prostheses. In the examination of these, the bending deformation and fluttering of heart valve cusps is an interesting and influential aspect. An analysis of the deformation can support the understanding of correlations between hemodynamics and occurring mechanical stress. This contribution describes an approach to determine the dynamic bending deformation of aortic heart valve bio-prostheses in high speed video recordings and to compare different fluttering characteristics. The bio-prostheses are recorded in an artificial circulation setup and observed during the opening and closure of a systolic phase. Based on a segmentation of the orifice area, a distance signal is derived for each cusp relative to a base line given by the commissure points. This distance signal describes the static bending deformation of the cusps in one image frame. By observing the deformation during the phase of maximal flow, the dynamics of the cusps can be determined over time. The resulting fluttering is quantified by a frequency analysis of the time dependent distance signal. Thus, significant fluttering characteristics can be modeled and compared.