弁周囲逆流モデルでのせん断流れによる血栓形成の可視化とその解析

抄録

TAVI (Transcatheter Aortic Valve Implantation) is a minimally invasive treatment for Aortic Stenosis. Although when PVL (Paravalvular Leaks) occurred after surgery, life prognosis worsens. In this research, we made a PVL model with clearance around the orifice and compare visualization of thrombus formation on PVL flow visualized by optical system and flow field is also analyzed by CFD. Experimental result showed that PVL model thrombus formation depend on the clearance size. That is, thrombus formation in large leak model start around the leakage, whereas thrombus formation in small leak model start around the orifice. According to the CFD result, it was found that vortex and contraction existed in the flow field. It turned out that the vortex became smaller as the leakage became larger, but the contraction flow became larger as the leakage increased. Next, the difference in thrombus formation rate (Rs) near the wall compared with the clearance size. As a result, it was found that the leakage is large, the Rs increase. It was suggested that small wake by large leakage flow affected thrombus formation.