LAUSR

OBJECTIVES Thoracic endovascular aneurysm repair (TEVAR) has become the current standard of care for emergent treatment of blunt traumatic aortic injuries (BTAI). Although aortic dilation of the infrarenal neck following EVAR for aortic aneurysms has been studied, changes in aortic diameter following TEVAR for BTAI is not well understood. This study aims to characterize changes in thoracic aortic diameter following stent graft placement in the setting of non-aneurysmal traumatic aortic injury. METHODS A single-center, retrospective review was performed involving patients presenting with BTAI treated with TEVAR. Only patients with at least 12 months follow-up were included. Aortic diameter, defined as the outer-to-outer diameter on 3D center-line imaging, was measured at six locations along the proximal and mid thoracic aorta. The first post-operative CT (≤1 month) served as a baseline from which interval measurements were compared. RESULTS Twenty patients with BTAI treated from 2011-2017 had adequate imaging available for review and were included in this study cohort. Median follow-up time was 46.8 (12-80, range) months. At latest follow-up, aortic dilation (AD) occurred at all measured locations within the endograft, starting from the proximal graft edge (0.62±0.69mm, p=.027) to the distal graft edge (1.21±1.28mm, p=.003). AD was most pronounced in the distal graft segment 2cm proximal to the distal graft edge, with a mean AD of 1.32±1.59mm (+5.3%, p<.001). At this location, AD was found to increase in a linear manner with an estimated rate of 0.67±0.20mm /year (p=0.006). The native aorta proximal and distal to the endograft was not found to significantly dilate during follow-up (p=.280-.897). 70% of patients were found to have AD >5%. The amount of aortic dilation was not found to be associated with either graft oversizing (p=.151) or age (p=.340). There were no cases of graft migration, erosion or endoleak. CONCLUSIONS Aortic dilation is a common benign finding after TEVAR for BTAI. AD is most pronounced at the near the distal end of the stent graft. In late-term follow-up, there are no known associated complications related to AD.