Hemodynamic consequences of TEVAR with different configurations of in-situ fenestration stents: a patient-specific CFD analysis.

This exploratory study aimed to utilize patient-specific computational fluid dynamics (CFD) simulations to evaluate and compare the hemodynamic effects of different fenestration stent configurations following in situ fenestration thoracic endovascular aortic repair (ISF-TEVAR). Six patient-specific aortic models (pre- and postoperative) were reconstructed from CTA images of three ISF-TEVAR patients with distinct fenestration stent configurations. The hemodynamic parameters of the aortic arch and its main branches (including pressure, flow velocity, flow volume, and vascular wall shear stress (WSS)) were systematically analyzed to evaluate the effects of the stent configuration. Marked increases in pressure drop and WSS were observed in the left subclavian artery (LSA) in cases with higher stent compression. Compared to forward-leaning stent orientation, a near-perpendicular insertion was associated with more pronounced complex and disordered flow patterns around the fenestration site. In this small case series, different fenestration stent configurations significantly influenced local hemodynamics, particularly in the LSA. Minimizing stent compression and, where anatomically feasible, adopting a forward-leaning orientation may help reduce adverse hemodynamic effects. These preliminary findings highlight the potential utility of patient-specific CFD simulation in preoperative planning for ISF-TEVAR, though further studies with larger cohorts are needed to validate these observations.