Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA.
Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA; Department of Mechanical Engineering, The Ohio State University, Columbus, OH, USA.
J Mech Behav Biomed Mater. 2019 Oct;98:163-171. doi: 10.1016/j.jmbbm.2019.06.016. Epub 2019 Jun 19.
Transcatheter aortic valve replacement (TAVR) is a life-saving alternative to surgical intervention. However, the identification of features associated with poor outcomes, including residual paravalvular leakage (PVL), leaflet calcification, and subclinical leaflet thrombosis, are cause to be concerned about valve durablilty (Mylotte and Piazza, 2015a, 2015b; Dasi et al., 2017; Makkar et al., 2015; Kheradvar et al., 2015a). The aim of this study is to optimize the potential of a hyaluronan (HA) enhanced polymeric transcatheter aortic valve (HA-TAV) that has promised to reduce blood damage causing-turbulent flow while maintaining durability. HA-enhanced linear low-density polyethylene (LLDPE) leaflets were sutured to novel cobalt chromium stents, size 26 mm balloon expandable stents. Hemodynamic performance was assessed in a left heart simulator under physiological pressure and flow conditions and compared to a 26 mm Medtronic Evolut and 26 mm Edwards SAPIEN 3. High-speed imaging and particle image velocimetry (PIV) were performed. The HA-TAV demonstrated an effective orifice area (EOA) within one standard deviation of the leading valve, SAPIEN 3.The regurgitant fraction (RF) of the HA-TAV (11.23 ± 0.55%) is decreased in comparison the Evolut (15.74 ± 0.73%) and slightly higher than the SAPIEN 3 (10.92 ± 0.11%), which is considered trace regurgitation according to valve standards. A decreased number of higher principal Reynolds shear stresses were shown for the HA-TAV at each cardiac phase. The HA-TAV is directly comparable and in some cases superior to the leading commercially available prosthetic heart valves in in-vitro hemodynamic testing.
经导管主动脉瓣置换术(TAVR)是一种替代外科手术的救命方法。然而,识别与不良预后相关的特征,包括残余瓣周漏(PVL)、瓣叶钙化和亚临床瓣叶血栓形成,是对瓣膜耐久性的担忧的原因(Mylotte 和 Piazza,2015a,2015b;Dasi 等人,2017;Makkar 等人,2015;Kheradvar 等人,2015a)。本研究旨在优化透明质酸(HA)增强聚合物经导管主动脉瓣(HA-TAV)的潜力,该瓣膜有望减少引起湍流的血液损伤,同时保持耐久性。HA 增强的线性低密度聚乙烯(LLDPE)瓣叶缝合到新型钴铬支架上,尺寸为 26mm 球囊可扩张支架。在生理压力和流量条件下,在左心模拟器中评估血流动力学性能,并与 26mm Medtronic Evolut 和 26mm Edwards SAPIEN 3 进行比较。进行高速成像和粒子图像测速(PIV)。HA-TAV 的有效瓣口面积(EOA)在 SAPIEN 3 领先瓣膜的一个标准差范围内。HA-TAV 的反流分数(RF)(11.23±0.55%)与 Evolut(15.74±0.73%)相比降低,略高于 SAPIEN 3(10.92±0.11%),根据瓣膜标准,这被认为是微量反流。在每个心动周期,HA-TAV 的较高主雷诺切应力数量减少。在体外血流动力学测试中,HA-TAV 与领先的商业可用人工心脏瓣膜直接可比,在某些情况下优于后者。