P.055 Experimental Study of the Effects of a New Non-Cylindric “Curved-Edged” Stent on Flow Characteristics in a Model of a Mild Arterial Stenosis

Abstract

Background and Methods

Restenosis remains a major concern in vascular stenting, especially for ostial lesions. The purpose of this study was to investigate whether a non-cylindric stent, (with curved edges), implanted upstream of a mild arterial stenosis could be beneficial by increasing blood flow velocity and by limiting the flow recirculation zone in the vicinity of the stenosis. Steady and pulsatile flow fields were investigated in an axisymmetric model of an ostially stented arterial segment followed by a 50% stenosis, in an in-vitro model employing flow visualization technique. The stenosis was located close to the tube entrance a certain distance apart. Two different tube-entrance geometries, modelling a stented arterial segment, were studied regarding their effect on flow patterns at various Reynolds numbers (Re = 300–800).

Results

A decrease 3–6% in flow recirculation region at the vicinity distally to a 50% stenosis was observed when the “curved-edged” stent was used in the models compared to the regular cylindric stent. Mean flow velocity was increased for both steady flow (especially at low resistance) and pulsatile flow (for higher resistance), when the curved-edged configuration was used instead of the regular stent (figure).

Conclusions

These effects induced by the new stent configuration could be important and may potentially contribute to the delay of restenosis processes, which remains to be clarified in-vivo.