Bianchi Matteo, Ghosh Ram P, Marom Gil, Slepian Marvin J, Bluestein Danny
Annu Int Conf IEEE Eng Med Biol Soc. 2015;2015:282-5. doi: 10.1109/EMBC.2015.7318355.
Calcific aortic valve disease (CAVD) is a cardiovascular condition that causes the progressive narrowing of the aortic valve (AV) opening, due to the growth of bone-like deposits all over the aortic root (AR). Transcatheter aortic valve replacement (TAVR), a minimally invasive procedure, has recently become the only lifesaving solution for patients that cannot tolerate the standard surgical valve replacement. However, adverse effects, such as AR injury or paravalvular leakage (PVL), may occur as a consequence of a sub-optimal procedure, due to the presence of calcifications in situ. Additionally, the crimping required for delivering the valve via stenting may damage the valve. The aim of the present study is to comparatively assess the crimping mechanics of the commercialized Edwards SAPIEN valve and an alternative polymeric valve (Polynova, Inc) and to evaluate the effect of different TAVR deployment positions using patient-specific numerical models. The optimal deployment location for achieving better patient outcomes was calculated and based on the interactions between the TAVR stent and the native AR. Results demonstrated that the Polynova valve withstands the crimping process better than the SAPIEN valve. Furthermore, deployment simulations showed the role that calcifications deposits may play in the TAVR sub-optimal valve anchoring to the AV wall, leading to the presence of gaps that result in PVL.
钙化性主动脉瓣疾病（CAVD）是一种心血管疾病，由于主动脉根部（AR）各处出现骨样沉积物，导致主动脉瓣（AV）开口逐渐变窄。经导管主动脉瓣置换术（TAVR）是一种微创手术，最近已成为无法耐受标准外科瓣膜置换术患者的唯一救命解决方案。然而，由于原位钙化的存在，手术效果欠佳可能会导致诸如AR损伤或瓣周漏（PVL）等不良反应。此外，通过支架输送瓣膜所需的压接可能会损坏瓣膜。本研究的目的是比较评估商业化的爱德华兹SAPIEN瓣膜和一种替代性聚合物瓣膜（Polynova公司）的压接力学，并使用患者特异性数值模型评估不同TAVR部署位置的效果。基于TAVR支架与天然AR之间的相互作用，计算出实现更好患者预后的最佳部署位置。结果表明，Polynova瓣膜比SAPIEN瓣膜更能耐受压接过程。此外，部署模拟显示了钙化沉积物在TAVR瓣膜与AV壁锚定欠佳中可能起的作用，导致出现间隙并引发PVL。
