Aortic Neck Angulations Decrease during and after Endovascular Aneurysm Repair

Purpose: To investigate whether suprarenal and infrarenal aortic neck angles change immediately after endovascular aneurysm repair (EVAR) or during follow-up. A change in aortic angulation influences the proximal stent-graft sealing and fixation zone, thereby possibly influencing the long-term results of EVAR. Methods: Forty-three EVAR patients (39 men; mean age 73 years, range 62–85) with preoperative, postoperative, and 1, 2, and 3-year follow-up computed tomographic angiography (CTA) data were selected from our center's vascular database. The suprarenal and infrarenal angulations on all CTAs were measured using a standardized 3-dimensional centerline method, which has a repeatability coefficient of 6.4° (20.2%) for the suprarenal angle and 6.2° (13.4%) for the infrarenal angle. Repeated measures analysis was used to test the effect of angulation over time, followed by a post-hoc analysis. Results: The mean suprarenal angulation was 28°±16° preoperatively, 22°±16° postoperatively, 19°±15° after 1 year, 17°±14° after 2 years, and 16±13° after 3 years (mean difference 5°, 9°, 11°, and 12°, respectively). The aortic suprarenal angle decrease was significant (all p<0.01) compared with the preoperative measurements at all time points. The mean infrarenal angulation was 50°±18° preoperatively and changed to 41°±15° postoperatively, to 39°±14° after 1 year, to 38°±14° after 2 years, and to 36°±14° after 3 years (mean difference 8°, 11°, 11° and 13°, respectively). The infrarenal aortic angle decrease was significant (all p<0.01) compared with the preoperative measurements at all time points. Conclusion: The aortic suprarenal and infrarenal angles decrease during EVAR and in the years after this procedure.