Status of Endovascular Aneurysm Sealing After 5 Years of Commercial Use

Endovascular aneurysm sealing (EVAS) using the Nellix Endovascular Sealing System was introduced commercially in 2013 with the aim of reducing the incidences of reintervention and late complications observed after conventional endovascular aneurysm repair (EVAR). In the 5 years since its commercial launch, the Nellix system has evolved in terms of its structure, instructions for use, and delivery technique. Complications, including migration and proximal endoleak, have been recognized and treatment strategies developed, although durability remains to be demonstrated. Prospective multicenter trials have shown a low incidence of type I endoleak and reintervention at 1-year follow-up, comparable to conventional EVAR with modern devices. Since the aneurysm sac is "actively managed" with EVAS, similar to open surgical repair, type II endoleaks are rare with the Nellix system. Unexpected benefits of active sac management with EVAS include reduced incidences of postimplantation syndrome and cardiac complications, with low all-cause mortality at 1 year. Less neck dilatation compared to EVAR has also been observed. The Nellix device and procedure continue to evolve, and further prospective studies are indicated. This article analyzes the current EVAS evidence to update our knowledge of this technique in the management of abdominal aortic aneurysm.