Long-term failure after EVAS in a real-life single center experience with the Nellix endograft.

Abstract Background Endovascular aneurysm sealing (EVAS) is an innovative alternative to conventional endovascular aneurysm repair (EVAR). EVAS relies on sac anchoring without proximal fixation to achieve sealing and should have allowed the treatment of a broader range of anatomies compared to standard EVAR. Despite encouraging early reports, mid- and long-term follow-up has shown increased rates of failure. To address the issue, the manufacturer introduced the revised IFU in 2016. This study reports the outcomes of this system after a median follow-up of 45 months. Methods Data for all the patients electively treated with EVAS at our institution were retrospectively collected. The patients were retrospectively reclassified according to the 2016 revised IFU of the device. All patients in this series underwent the procedure for the treatment of infrarenal abdominal aortic aneurysm (AAA). The primary endpoint was therapeutic failure: graft migration > 5 mm, sac expansion > 5 mm, type IA endoleak (Is2 and Is3 according to Van den Ham classification) and IB endoleak, and secondary rupture. Overall mortality, aortic-related mortality and reintervention rates were also analyzed. Results 101 patients were electively treated by EVAS between 2013 and 2018 for infrarenal AAA. Median follow-up was 3.75 years. Therapeutic failure was observed in 30.7% of patients (31/101) with no significant difference between the in- and off-IFU 2016 subgroups. Failure occurred at a median interval of 34 months from the index procedure. 6.9% of patients presented secondary rupture. Freedom from aneurysm-related mortality was 96.9% at 1 and 2 years and 89.9% at 5 years. Freedom from reintervention dropped over time: 94.7% at 1 year, 77% at 4 years and 52.1% at 6 years. 13.9% (14/101) of the whole cohort underwent emergent or elective graft explantation. Conclusions EVAS performed worse than conventional endografts on several critical endpoints regardless of any preoperative anatomic parameters. Therapeutic failures tend to increase over time, especially 4 years after the index procedure.