Midterm Outcomes With the Nellix Endograft Alone or With Chimneys

Abstract

Endovascular aneurysm sealing (EVAS) appeared to be an innovative alternative to conventional endovascular abdominal aortic aneurysm repair. However, high rates of mid-term failure of the EVAS led to withdrawal of the device from the market. The study aim was to report mid-term outcome of patients treated with EVAS alone or associated with chimneys (ChEVAS) and their management complications. In this single centre study, all consecutive Nellix between 2013 and 2016 were included. Primary endpoint was device failure: (1) a triad of caudal migration of the Nellix stents > 5 mm, separation of the endobags (> 5 mm), and sac enlargement (> 5 mm), with or without visible endoleak, (2) secondary rupture of the aneurysm, (3) surgical explant of the graft, or (4) any intervention for a type I endoleak. Overall mortality, aneurysm related mortality, and re-intervention rates were analysed. Fifty patients (male n = 43, female n = 7) were included. Median follow up was 3.05 years (interquartile range [IQR] 0.52, 4.63) and follow up index was 0.51 (IQR 0.10, 0.88). Device failures occurred in 17 patients (34%). Overall and aneurysm related mortality during the follow up period were 30% and 13%. Fourteen (28%) patients required re-interventions. Five EVAS patients (17.2%) presented with complications. Type Ia were managed by device explantation for three patients, and endovascular aneurysm repair in Nellix for two patients. Type Ib endoleak was managed with an iliac branched device and limb extension. Nine ChEVAS patients (42.9%) presented with complications. Type Ia was managed by Nellix stent prolongation and renal extension, two multibranched thoraco-abdominal devices, and two device explantations. Type Ib endoleak was managed by limb extension and stent complications by stent angioplasty and ilio-renal bypass. Mid-term outcome of EVAS is poor. All patients who underwent EVAS implantation must be informed and should undergo frequent surveillance. Open repair and device explantation should be considered as the primary treatment.