Technical Considerations and Preliminary Experience of Intraprocedural Aneurysm Sac Embolization During Fenestrated and Branched EVAR (Embo F/BEVAR Technique): A Case Series

<b>Background:</b> The aim of this case series is to describe technical considerations and preliminary outcomes of preventive aneurysm sac embolization during fenestrated or branched EVAR (embo F/BEVAR technique). <b>Methods:</b> Five male patients suffering from juxtarenal or pararenal abdominal aortic aneurysms, preoperatively identified as being at "high risk" of type 2 endoleak (EL2) development, were treated with embo F/BEVAR. The patients presented at least two of these risk factors: patent inferior mesenteric artery (IMA) > 3 mm; more than three pairs of patent lumbar arteries (LAAs); more than two pairs of LAAs, associated with an accessory efferent artery or at least a pair of intercostal arteries; aneurysm thrombus volume < 40%; aneurysm sac diameter > 65 mm. Embo F/BEVAR was performed with 15 × 20 mm MReye Inconel coils (Cook Medical, Limerick, Ireland), using different aortic endografts. <b>Results:</b> Technical success was 100%, with no complications related to perioperative or postoperative coils implantation. An average number of 11 ± 4.4 coils/patient was deployed. No reinterventions were observed during the follow-up (12.4 ± 3.6 months). One case of EL2 (20%) was detected during the follow-up, without aneurysm sac enlargement. <b>Conclusions:</b> According to this preliminary experience, embo F/BEVAR technique with Inconel coils seems a feasible adjunctive procedure to manage the risk of EL2 after FEVAR or BEVAR, allowing a simple follow-up with low levels of scatter artifacts, and ensuring limited additional procedural costs. Moreover, embo F/BEVAR can be used with different endografts, requiring minimal increases in operating times. Further studies with larger cohorts of patients and longer follow-up periods are mandatory to better define the potential of this technique and its limitations.