Background: Abdominal aortic aneurysm with severe infrarenal neck angle (>60°) has long been thought to be an obstacle to endovascular aneurysm repair. However, some previous studies reported endovascular aneurysm repair to be safe and efficacious for treating abdominal aortic aneurysm in patients with severe neck angulation. The aim of this study was to investigate the early and late outcomes of endovascular aneurysm repair to treat abdominal aortic aneurysm compared between patients with severe and non-severe infrarenal neck angulation.
Methods: Fifty-four severe and 144 non-severe neck angulation patients who were treated at Siriraj Hospital (Bangkok, Thailand) during January 2010-October 2013 were recruited. The primary endpoints were intraoperative neck complications (e.g., type 1A endoleak or proximal graft migration) and immediate adjunct aortic neck procedures. The secondary endpoints included perioperative mortality, overall survival, and the proportion of patients that were reintervention-free at five years compared between the severe and non-severe groups.
Results: Severe angulation patients were significantly older than non-severe angulation patients (77 ± 6.3 vs. 74 ± 7.9 years; p = 0.021). The median proximal angle was significantly greater in the severe group (82° vs. 13.5°; p < 0.001). Intraoperative proximal neck complications developed in 29.6% of patients in the severe angulation group compared with 9.0% in the non-severe group (p < 0.001). Significantly more patients in the severe group required intraoperative adjunct procedures (29.6% vs. 7.6%; p < 0.001). There was no significant difference in perioperative mortality between groups. At the five-year follow-up, there was no significant difference between groups for overall survival or the proportion of patients that remained reintervention-free.
Conclusions: Endovascular aneurysm repair to treat abdominal aortic aneurysm in patients with severe proximal neck angulation is technically feasible and safe Although the severe angulation group had a higher rate of intraoperative neck complications and immediate adjunct neck procedures than the non-severe group, there was no significant difference between groups for 30-day mortality, overall survival or the proportion of patients who remained reintervention-free at five years.
Keywords: Abdominal aortic aneurysm; endovascular aneurysm repair; severe proximal neck angulation.