Mechanistic study of annular eccentricity-induced flow instability and thrombus growth in TAVI patients: a geometric...

This study investigates the potential hemodynamic penalty of post-TAVI annular eccentricity on thrombogenesis. By integrating patient-specific CTA data with a computational framework coupling multi-component transport equations and the Momentum Sink Method, we compared hemodynamics and thrombus burden between idealized circular and controlled elliptical models. Our analysis suggests that elliptical morphology may significantly alter coherent helical flow, leading to more fragmented eddies within the sinuses. This hemodynamic alteration is associated with statistically elevated mean Relative Residence Time (RRT) and Endothelial Cell Activation Potential (ECAP) ( $P<0.05$ ), which correlated with an observed increase in simulated thrombus volume and surface area. These findings indicate that annular eccentricity could be a significant, biology-independent geometric factor contributing to post-TAVI thrombotic risk. Our results propose that incorporating annular morphology into postoperative assessments may provide complementary biomechanical insights for individualized anticoagulant management.