Migration of the Nellix endoprosthesis

Abstract

PURPOSE: To report the incidence and sequelae of migration of the Nellix® endoprothesis following endovascular aneurysm sealing (EVAS).METHOD: A review was performed of the follow-up imaging of all EVAS patients in a University Hospital endovascular programme who had a minimum follow-up of one year. Using the first post-operative and latest follow-up CT scans, the distances between the proximal and distal borders of the stent-grafts relative to reference vessels were measured using a previously validated technique. Device migration was based on previously established criteria and defined as any stent-graft movement of ≥ 4 mm related to a predefined reference vessel. Device movement in a caudal direction was given a positive value (+) whereas movement in a cranial direction was denoted by a negative sign (-).RESULTS: 18 patients (35 stent-grafts) were eligible for inclusion in this retrospective review.The mean (SD; range) pre-operative AAA diameter and aortic neck length were 57 (5; 50 to 67) mm and 30 (16; 6 to 62) mm, respectively. Proximal migration, according to study definitions, was identified in six stent-grafts (17%), all in a caudal direction. At one year the mean (SD; range) proximal migration distance was +6.6 (1.6; +4.7 to +9.2) mm. Migration occurred in a single stent-graft in four patients and bilaterally in one. Distally, there were no cases of migration.CONCLUSIONS: Proximal migration of the Nellix® endoprosthesis does occur and in our series was without any sequelae. Further investigations into the long-term positional stability of the Nellix® device are required together with a more thorough understanding of the aetiology and consequences of migration.

Nellix stent graft migration after endovascular aneurysm sealing

“…Proximal migration of the Nellix endoprosthesis has been reported to occur in 17 % of cases [6]. In our case, a small type Ia endoleak was initially identifi ed on the 1-month surveillance CT. After discussion at our MDT meeting, we decided to deviate from our local surveillance protocol to closely monitor the endoleak.…”

Editor's Choice – Occurrence and Classification of Proximal Type I Endoleaks After EndoVascular Aneurysm Sealing Using the Nellix™ Device

“…The incidence of migration is largely unknown, although a > 4 mm displacement was described in five of 18 EVAS treated patients. 13 At 1 year, core laboratory adjudicated migration >10 mm occurred in three patients (2.3%) in the Nellix system IDE pivotal trial. 9 Migration was not reported in the 12 month outcome of the EVAS FOR-WARD Global Registry, 10 but this was only site reported.…”

Anatomical Applicability of Endovascular Aneurysm Sealing Techniques in a Consecutive Cohort of Fenestrated Endovascular Aneurysm Repairs

“…While there is limited knowledge of factors that lead to poor outcomes following ChEVAS, in our cohort the majority of the 56 technically feasible EVAS cases were judged to be outside the current infrarenal IFU 20 regarding thrombus diameters, which have been recently updated owing to the risk for migration. 21 This represents a recent development in EVAS knowledge and is a reminder that technical applicability should not be conflated with clinical appropriateness.…”