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Editorials published in the Journal of Endovascular Therapy reflect the opinions of the author(s) and do not necessarily represent the views of the Journal, the InternatIonal SocIety of endovaScular SpecIalIStS, or SAGE Publications Inc. Innovation is the cornerstone of surgical practice. Consider the aortic stent-graft. After years of experimental and clinical research during the 1980s by Volodos and colleagues in Ukraine, endovascular aneurysm repair (EVAR) was introduced to the West in the early 1990s. It has since transformed the management of aortic aneurysm. The impressive 30-day mortality and short-term outcomes achieved with EVAR enabled the treatment of patients who would otherwise have been considered unfit for intervention. Indeed, the short-term gains observed with elective infrarenal EVAR have been echoed in the IMPROVE trial, which also concluded that EVAR was efficacious and cost effective for ruptured infrarenal abdominal aortic aneurysm (AAA). With such significant improvement in short-term outcomes, medical device companies quickly began competing to bring new, innovative endografts to market. Concerns about the long-term durability of EVAR are not new, but proponents have argued that historical data with old technology does not accurately reflect current practice. The early adoption of new aortic stent-grafts has increased significantly; as of 2010, EVAR accounted for 74% of AAA repairs in the United States. Fifteen-year follow-up data of the EVAR 1 trial has made for uncomfortable reading. Beyond 8 years there was a significant survival advantage for open AAA repair. Furthermore, EVAR was associated with more reinterventions and a high burden of surveillance. These data have recently been corroborated by a large series from the United Kingdom of over 38,000 unruptured AAA repairs collected by the UK Hospital Episode Statistic. EVAR was associated with higher 10-year mortality and higher risk of rupture over 9 years than open surgical repair (3.4% vs 0.9%). Endoleak remains a major factor in reducing the longterm durability of EVAR. Types I and III endoleaks require prompt intervention, and type II endoleaks should be treated in the presence of significant sac enlargement to reduce the risk of secondary sac rupture. To address this complication, the revolutionary technique of endovascular aneurysm sealing (EVAS) was developed to obliterate the aneurysm sac. The Nellix EVAS system (Endologix Inc, Irvine, CA, USA) consists of balloon-expandable stent-grafts surrounded by endobags containing a polymer that was designed to fill the aneurysm sac and eliminate space for endoleak formation; there is no proximal fixation. The pivotal trial investigating the safety and efficacy of Nellix EVAS reported encouraging 30-day and 1-year outcomes, which led to marketing approval in the United States. These trial outcomes were confirmed in larger real-world multicenter cohorts. EVAS was reported to be quick to deploy, with reduced radiation exposure to patient and operating team. Unfortunately, longer-term follow-up demonstrated significant failure rates beyond 2 years after EVAS implantation. Higher incidences of type Ia endoleak, graft migration, and secondary sac rupture were reported in the EVAS FORWARD investigational device exemption (IDE) trial, which resulted in refinement of the instructions for use (IFU). Significant midterm failures were reported by Harrison et al at a large-volume UK tertiary center. In this cohort, device failures were seen in 26% of patients, rates alarmingly higher than for EVAR. Further data from United Kingdom and Europe supported these findings. In light 886338 JETXXX10.1177/1526602819886338Journal of Endovascular TherapySingh and Boyle research-article2019