Hemodynamic Parameters Predict the In-Stent Thrombosis After the Multibranched Endovascular Repair for Complex Abdominal Aortic Aneurysms: A Preliminary Study on Branched Stent-Graft Thrombosis.

Abstract

Backgrounds: Branched vessel occlusion is frequently reported in the endovascular repair for aortic pathology. This study aimed to evaluate the hemodynamic indicators associated with the in-stent thrombosis (IST) of the branched stent-graft (BSG) after the endovascular aortic repair (EVAR) for complex abdominal aortic aneurysm.Methods: A retrospective evaluation was performed based on the computed tomography (CT) scan and clinical data of three patients who underwent multibranched endovascular repair. The reconstruction of patient-specific 3-dimension models and hemodynamic analysis for IST were performed. The hemodynamic related parameters including time-averaged wall shear stress (TAWSS), oscillatory shear stress index (OSI) and relative residence time (RRT) were compared between the individual data.Results: The velocity, TAWSS, OSI and RRT were radically changed in the area of IST. The IST of the BSG were located at the hemodynamic alteration regions near the bending curve where the decreased flow velocity (<0.6 m/s), TAWSS (<0.8 Pa) and elevated OSI (>0.3), and RRT (>5 s) were constantly observed. Conclusions: The hemodynamic perturbations in the BSG predispose the IST, which could be predicted by a series changes of the flow parameters. Early hemodynamic analysis might be useful for identifying and remediating the IST after the multibranched endovascular repair.Trial registration: This study was retrospectively registered and approved by the institutional ethical review board.