Inaccurate aortic stent graft deployment in the distal landing zone: incidence, reasons and consequences

The aim of this study was to investigate the accuracy of stent graft deployment in the distal landing zone (LZ) during thoracic endovascular aortic repair (TEVAR). Currently, TEVAR focuses on accurate stent graft deployment in the proximal LZ. Data on landing in the distal LZ are lacking.

Of 195 TEVAR patients (2005-16) with a non-dissected aortic pathology, 59 [median age 73 years (first quartile 68; third quartile 77), 20 women] patients had a distal LZ shorter than 40 mm. In all, the aim was to deploy the stent graft just above the target vessel (coeliac trunk, mesenteric superior or renal artery). Patients were divided into the accurate landing (n = 10) and inaccurate landing (IAL, n = 49) groups according to the distance to the target vessel ≤ 5 mm or > 5 mm after TEVAR, target vessel coverage and the need for a second stent graft in the distal LZ. We assessed the distal LZ, stent graft distance to the target vessel, apposition, migration and endoleak Ib on computed tomography. Median follow-up period was 23 months (5; 48).

Distal LZ anatomy did not differ between groups. Overall stent graft distance to the target vessel was 10.0 mm (6.5 mm; 16.0 mm). Three patients required a second stent graft in the distal LZ, and in 3 others, the target vessel was accidentally covered. In patients of the accurate landing group primary endoleak Ib occurred less frequently than those in the IAL group (0% vs 33%; P = 0.049). Three (30%) accurate landing and 19 (39%) IAL patients (P = 0.73) presented with substantial stent graft wedge apposition.

Accurate stent graft implantation in the distal LZ with the currently available deployment mechanism is often challenging. An inaccurate landing is associated with a higher incidence of endoleak Ib.