Chimney with the Use of Nellix Device: An Alternative Solution for Type I Endoleak Treatment

Abstract

Introduction - Endovascular aortic repair with chimney technique (Ch-EVAR) is commonly used in the treatment of type I endoleak when the patient is unsuitable for conversion to open surgery or custom made endograft implantation. Main issue with chimney technique is related to gutter endoleak; this risk may be reduced with the use of a Nellix device (Ch-EVAS), that could fill the gutter and reduce the incidence of type I endoleak. Methods - Sixteen consecutive patients (mean age 80.7 ± 7.0 years; 94% men) with prior EVAR were treated with ChEVAS between August 2015 and March 2018 in a single center. Indication for treatment was proximal type I endoleak in all patients, with associated neck dilation in 5 patients and migration in 5. The median diameter of residual aneurismal sac was 79.1 ± 2.4 mm The median time between original procedure and ChEVAS was 92.7±5.3 (range 1-148) months. Prior EVARs included different endografts (5 Zenith, 3 Endurant, 4 Talent, 1 Anaconda, 1 Fortron and 2 Nellix). In 12 patients (75%) preoperative CT scan showed the presence of suprarenal stent at the level of the visceral vessels. Two patients needed one chimney, ten patients needed double chimney and four patients needed three chimneys for a total of 34 target vessel overstented. In 30 visceral vessels a balloon expandable stent (Advanta atrium or Bentley BeGraft) was implanted, in the remaining 4 vessels a self-expandable stent (Viabahn Gore) was delivered. The Nellix endograft was implanted by bilateral percutaneous femoral approach in 11 patients Results - Technical success was achieved in 100% of the patients by completion angiography at the end of the procedure. No perioperative mortality was observed, one patient experienced non disabling posterior stroke at the end of the procedure. CT scan performed 1 month after the procedure showed sealing of 15/16 (94%) of type I endoleak , the remaining patient with residual proximal endoleak underwent a successful Onyx embolization one month later. At median follow-up of 13 months no recurrent endoleaks were recorded. All target vessel stented were patent with no need of reintervention. Conclusion - ChEVAS may serve as alternative treatment option in patients with type I endoleak where the implantation of fEVAR/brEVAR is hampered by the presence of previous endograt in site. Further follow-up and a multicenter study are needed to corroborate these preliminary results