High Speed Video Study of the Valve Leaflet Motion of the ePTFE Valve Conduit: Influence of the Bulging Sinus Size of the Valve Conduit on the Valve Opening Area and Flow Field

10.6567/IFToMM.14TH.WC.PS1.006

T. Akutsu；K. Okuyama

RVOT ； ePTFE valve ； PIV ； Sinus of Valsalva

Proceedings of the 14th IFToMM World Congress

14th-5（2015 / 11 / 06）

61 - 64

英文

Good clinical records seem to show expanded polytetrafluoroethylene (ePTFE) valve conduits may be a good choice for treating right ventricular outflow tract (RVOT) reconstruction in congenital heart defects. Bulging sinus of the ePTFE valve seem to have favorable effect on hemodynamic performance, however, fluid mechanical research proving this effect has been limited. This research aims to study the effect of the bulging sinus size of the ePTFE valve on the valve opening area and flow phenomenon inside the conduit. Several valve conduit models with different bulging sinus sizes were used. Straight model, 50% reduced model, 25% reduced model, normal model, and 50% enlarged model were prepared. Effect of the bulging sinus size on a flow field inside the valve conduit was analyzed using Dynamic PIV system running at 1900 frames/s and valve opening areas were directly recorded using high speed digital camera running at 300 frames/s. Comparison of flow field results showed that the flow field of valve conduits with normal and 50% enlarged model generated strong vortex immediately behind the leaflet edge. Valve opened and closed early with normal and 50% enlarged model compared to 50% reduced model. Direct observation of the opening area of the valve showed that wider opening area was observed with normal and 50% enlarged model. Relative location of vortex seems to play important roll on valve open and close mechanism.