Anatomic predictors of distal landing zone failure after endovascular repair of thoracic aortic aneurysm†.

Objectives: To analyse anatomic factors of the distal landing zone (dLZ) associated with the durability of endovascular repair of thoracic aortic aneurysm (TAA).

Methods: Consecutive patients undergoing thoracic endovascular aortic repair (TEVAR) for undissected TAA were queried from a single centre from 2004 to 2022. Patient and operative factors were considered as well as detailed anatomic factors at the dLZ assessed by 3D reconstruction of pre-TEVAR imaging. The outcome of interest was the long-term risk of TEVAR failure at the dLZ.

Results: A total of 101 patients undergoing TEVAR repair of TAA were considered, of whom 17 suffered distal TEVAR failure over a median follow-up period of 2.7 years. Two anatomic factors showed outsized influence on long-term outcomes: dLZ diameter and dLZ length (the length of non-dilated aortic tissue above the coeliac artery). Patients who progressed to distal TEVAR failure had larger dLZ diameter (34.2 mm vs 30.7 mm, P = 0.034) and far shorter dLZ length (3.8 cm vs 7.5 cm, P = 0.008). Patients with dLZ diameter greater than 35 mm had much greater risk of mortality or distal TEVAR failure within 2 years (34% vs 5%, P = 0.012), as did those with dLZ length less than 4 cm (27% vs 6%, P = 0.006).

Conclusions: In this study, mild dilation at the dLZ beyond 35 mm and short length at the dLZ less than 4 cm are both clear anatomic risk factors for poor long-term outcome after supraceliac TEVAR. It may be appropriate to consider repair via branched endografts landing beyond the coeliac artery in patients with these risk factors.