Biomechanical mechanism of distal stent-graft-induced new entry deterioration after thoracic endovascular aortic repair

Abstract

Stent-grafts are bringing new life to aortic dissection patients through thoracic endovascular aortic repair (TEVAR). However, various postoperative complications are threatening the recovery of patients and even require clinical reintervention. The objective of the present study is to reveal the biomechanical mechanism of distal stent-graft-induced new entry (dSINE) deterioration after TEVAR. Six patients treated by TEVAR were collected from the clinical hospital, and dSINE was observed in the follow-up of all patients, which are evenly divided into two groups. The dSINE in the control group was stable while the patients in the experimental group continued to deteriorate and experienced reintervention. Computational fluid-structure interaction hemodynamics were performed in the above patients based on clinical images of early dSINE. The results show that time-averaged wall shear stress or oscillatory shear index alone fails to accurately forecast the deterioration of dSINE. While relative residence time and endothelial cell activation potential demonstrate stronger predictive power and the former seems to be better. Additionally, the region exposed to high von Mises stress and significant wall deformation is also associated with further dSINE deterioration. In conclusion, this study highlights that the postoperative biomechanical environment can predict the further development of dSINE, which is conducive to assisting physicians in improving the risk stratification of dSINE and customizing a follow-up plan.