Introduction: The aim of the present study is to report the outcome of patients presenting an isolated type II endoleak (TIIEL) requiring reintervention and to identify clinical and anatomical characteristics potentially implicated in refractory TIIEL occurrence and fate. Materials and Methods: A multicenter retrospective study on TIIEL requiring reintervention was conducted between January 2003 and December 2020. Demographic and clinical characteristics, procedural technical aspects, reinterventions, and outcomes were recorded. TIIEL determining sac expansion greater than 10 mm underwent a further endovascular procedure aiming to exclude aneurismal sac. Redo endovascular procedures were performed via endoleak nidus direct embolization and/or aortic side branches occlusion. TIIELs responsible for persisting aneurysmal sac perfusion 6 months after redo endovascular procedures were classified as “refractory” and submitted to open conversion. Results: A total of 102 TIIEL requiring reintervention were included in the final analysis. Eighty-eight (86.27%) patients were male, the mean age was 77.32 ± 8.08 years, and in 72.55% of cases the American Society of Anaesthesiologists (ASA) class was ≥3. The mean aortic diameter was 64.7 ± 14.02 mm, half of treated patients had a patent inferior mesenteric artery (IMA), and 44.11% ≥ 3 couples of patent lumbar arteries (LA). In 49 cases (48.03%) standard endovascular aneurysm repair (EVAR) procedure was completed without adjunctive maneuvers. All enrolled patients were initially submitted to a further endovascular procedure once TIIEL requiring reintervention was diagnosed; 57 patients underwent LAs or IMA embolization (55.87%), 42 transarterial aneurismal sac embolization (41.17%), and three (2.96%) laparoscopic ostial ligations of the inferior mesenteric artery. During a mean follow-up of 15.22 ± 7.57 months (7–48), a redo endovascular approach was able to ensure complete sac exclusion in 52 cases, while 50 patients presented a still evident refractory TIIEL and therefore a surgical conversion or semiconversion was conducted. At the univariate analysis refractory TIIEL patients were significantly different from those who did not develop the complication in terms of preoperative clinical, morphological characteristics, and initial EVAR procedures: coronary artery disease occurrence (p = 0.005, OR: 3.18, CI95%: 1.3–7.2); preoperative abdominal aortic aneurysm (AAA) sac diameter (p = 0.0055); IMA patency (p = 0.016, OR: 2.64, CI95%: 1.18–5.90); three or more patent LAs; isolated standard EVAR without adjunctive procedures (p > 0.0001; OR: 9.48, CI95%: 3.84–23.4). Conclusions: Our experience seems to demonstrate that it is reasonable to try to preoperatively identify those patients who will develop a refractory TIIEL after EVAR and those with a TIIEL requiring reintervention for whom a simple endovascular redo will not be enough, needing surgical conversion.

Objective: Knowledge of hostile factors and their influence on long-term seal in the iliac landing zone is limited. Currently endorsed clinical practice guidelines lack structural evidence on how the iliac landing zone should be assessed in the pre-, intra-, and postoperative phases. The goal of this study was to obtain an international, expert-based consensus on the definition of a hostile iliac landing zone, on how to size and plan stent-grafts to optimize sustainable distal seal, and on the postprocedural follow-up protocol. Methods: Delphi consensus methodology was used, involving a panel of international vascular surgeons experienced in endovascular aneurysm repair (EVAR). The first round consisted of open-ended and multiple-choice questions to explore current practices, with subsequent rounds refining statements through a 4-point Likert scale. Consensus was defined as >75% agreement or disagreement, and the analysis included stability testing and strength of consensus. Results: The study engaged 77 international vascular surgeons, reflecting diverse geographic locations and hospital affiliations. Consensus was achieved on critical preoperative planning elements for EVAR, including a clear definition for a hostile iliac landing zone. The importance of computed tomography angiography for postoperative follow-up imaging was emphasized, including evaluating distal seal length and recommending specific timing for follow-up computed tomography scans and intervention strategies for diminishing iliac seal. Conclusions: This international expert-based Delphi consensus establishes a comprehensive set of consensus-driven recommendations focused on the definition and management of hostile iliac landing zones in EVAR. The key recommendation of this study is the definition of a hostile iliac landing zone as short (24 mm), or conical (>10% diameter difference along the landing zone). Although consensus was achieved on several critical aspects, the study also reveals ongoing debates and considerations that warrant further exploration, including how to tackle diminishing seal without a type IB endoleak. Clinical Impact: This Delphi consensus introduces a standardized definition of a hostile iliac landing zone as short (24 mm), or conical (>10% diameter difference), clinicians now have a clearer framework for assessing complex anatomies. This study provides a comprehensive set of consensus-driven recommendations focused on the definition and management of hostile iliac landing zones in EVAR which gives guidance where current guidelines lack specificity, particularly for distal iliac sealing. The study also reveals ongoing debates and considerations that warrant further exploration, including how to tackle diminishing seal without a type IB endoleak.