Preliminary Results of aMulticenter Experience With NELLIX System for Endovascular Aneurysm Sealing. Italian Research Nellix-Endoprosthesis-IRENE Investigators Frigatti P, Angiletta D, Bellandi G, Marconi M, Galzerano G, Garriboli L, Grossi R, Iannello AM, La Barbera A, Martinelli O, Novali C, Pulli R, Setacci C, Speziale F, Talarico F, TaurinoM

Results Conclusions Go Objectives Due to advances in technology and operator experience, endovascular aneurysm repair (EVAR) has supplanted open repair to treat abdominal aortic aneurysms. However traditional EVAR is associated short- and long-term complications, including a relevant rate of secondary interventions and open conversions for endoleaks and endograft migration. The Nellix system (Endologix Inc, Calif) with endovascular aneurysm sealing has been developed to address several EVAR limitations by sealing the aneurysm sac, therefore stabilizing the endograft position. We report the short-term results of a retrospective, multicenter study with EVAS in both elective and emergency settings. The aims of this study included technical success, procedure-related mortality, endoleaks, devices integrity, reinterventions, and aneurysm-related complications. Go Methods From September 2013 to November 2015, 335 patients (median age, 74 years, 315 males) were treated with the Nellix device at 16 Italian vascular centers, according to each endovascular aneurysm repair protocol. EVAS was carried out electively in 330 cases (98.5%). Among all patients, 87.2% fulfilled the standard instructions for use of the Nellix system. Preoperative mean aneurysm diameter was 57 mm (range, 43-74 mm), with a mean aneurysm blood lumen diameter of 36 mm (range, 30-50 mm). Infrarenal aortic mean neck length was 24 mm (range, 0-59 mm); mean neck angle was 42° (range, 10°-66°). The inferior mesenteric artery, and one or more pairs of lumbar arteries emerging from the aneurysmal sac were patent in 61.8% and in 81.3% of cases, respectively. Surgical femoral cutdown was performed in 54.9% of cases and percutaneous access in 45.1%. Prefilling of the Nellix endobags was always carried out, and mean polymer intrasac pressure was 194. 6 mm Hg. In the first 30 days, all patients underwent duplex ultrasound either contrast-enhancement ultrasounds. Contrast computed tomography and/or magnetic resonance controls were carried out following local standards of care. Go Results Procedure-related mortality was nil; procedural success was 100%. No postoperative endoleak was observed. Early complication included 5 (1.5%) type I endoleaks, 2 treated and 3 under observation; 3 (0.9%) untreated type II endoleaks; 3 (0.9%) unilateral stent occlusions, submitted to thrombolysis in 2 and to thrombectomy in 1; 7 (2.1%) distal embolism, treated in all cases but 1; 2 (0.6%) incidental occlusion of the hypogastric arteries; and 2 common femoral artery dissections promptly corrected. Go Conclusions Based on this initial multicenter experience, the Nellix system has the potential to address many limitations and to minimize the risk of endoleak of traditional EVAR, with high technical success and low incidence of procedure-related complications and reinterventions. These data seem to be confirmed by our 1-year follow-up, already available in 133 cases.