Bicuspid aortic valve (BAV) anatomy has routinely been considered an exclusion in the setting of transcatheter aortic valve implantation (TAVI) because of the large dimension of the aortic annulus having a more calcified, bulky, and irregular shape. The study aims to develop a patient-specific computational framework to virtually simulate TAVI in stenotic BAV patients using the Edwards SAPIEN 3 valve (S3) and its improved version SAPIEN 3 Ultra and quantify stent frame deformity as well as the severity of paravalvular leakage (PVL). Specifically, the aortic root anatomy of n.9 BAV patients who underwent TAVI was reconstructed from pre-operative CT imaging. Crimping and deployment of S3 frame were performed and then followed by fluid-solid interaction analysis to simulate valve leaflet dynamics throughout the entire cardiac cycle. Modeling revealed that the S3 stent frame expanded well on BAV anatomy with an elliptical shape at the aortic annulus. Comparison of predicted S3 deformity as assessed by eccentricity and expansion indices demonstrated a good agreement with the measurement obtained from CT imaging. Blood particle flow analysis demonstrated a backward blood jet during diastole, whereas the predicted PVL flows corresponded well with those determined by transesophageal echocardiography. This study represents a further step towards the use of personalized simulations to virtually plan TAVI, aiming at improving not only the efficacy of the implantation but also the exploration of "off-label" applications as the TAVI in the setting of BAV patients. Graphical abstract Computational frameworks of TAVI in patients with stenotic bicuspid aortic valve.

中文翻译：

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狭窄性双尖瓣主动脉瓣患者经导管心脏瓣膜植入的模拟研究。

由于主动脉瓣环的尺寸较大，钙化，膨大和不规则形状，通常认为双尖瓣主动脉瓣（BAV）解剖是经导管主动脉瓣植入（TAVI）的一种排除方法。这项研究旨在开发一种针对患者的计算框架，以使用Edwards SAPIEN 3瓣膜（S3）及其改良版SAPIEN 3 Ultra在狭窄的BAV患者中虚拟模拟TAVI，并量化支架框架畸形以及瓣周漏的严重程度（PVL） ）。具体而言，从术前CT成像重建了9例行TAVI的BAV患者的主动脉根部解剖结构。进行S3框架的压接和展开，然后进行流固耦合分析，以模拟整个心动周期中瓣膜小叶的动力学。模型显示，S3支架框架在BAV解剖结构上扩展良好，主动脉瓣环呈椭圆形。通过偏心率和膨胀指数评估的预测S3畸形的比较与从CT成像获得的测量结果吻合良好。血液颗粒流分析表明在舒张期出现了反向的血流，而预测的PVL流量与经食管超声心动图测定的血流非常吻合。这项研究代表了使用个性化仿真来虚拟计划TAVI的又一步，不仅旨在提高植入的疗效，而且还探索了在BAV患者中作为TAVI的“非标签”应用的探索。狭窄性双尖瓣主动脉瓣患者中TAVI的图形化抽象计算框架。