Chimney Versus Fenestrated Endovascular Versus Open Repair for Juxta/Pararenal Abdominal Aortic Aneurysms: Systematic Review and Network Meta-analysis of the Short-term Results

Physician-Modified Endografts for Non-deferrable Complex Abdominal Aortic Aneurysm Repair Using the Endurant Platform: Templates and Initial Results

INTRODUCTION AND OBJECTIVES

Complex abdominal aortic aneurysm (AAA) repair often requires the use of fenestrated and branched endografts, which can be influenced by factors such as device availability, cost, and operator expertise. This study aims to evaluate the preliminary results with physician-modified endografts (PMEGs) utilizing the Medtronic Endurant platform.

METHODS

Retrospective analysis of consecutive patients unsuitable for other techniques or custom-made devices, in which a PMEG Endurant was used for repair between 2021 and 2024. Bidimensional templates of the Endurant endograft were developed to ensure precise fenestration placement, which was confirmed intraoperatively with a 3D-printed aortic template. Endpoints were technical success, mortality, reinterventions, and target vessel patency.

RESULTS

Thirty-seven target vessels in 18 patients (mean age 79.4 ± 9 years, 94% male) were treated with Endurant main bodies (n=10, 55.6%), abdominal tubes (n=4, 22.2%), or aortic extensions (n=4, 22.2%). Mean aneurysm diameter was 70.0 ± 23 mm. Mean number of fenestrations was 2.1 ± 1 (33.3% 3-FEN or 4-FEN). The most frequent bridging stents were iCover (n=15, 40.5%), BeGraft (n=10, 27.0%), and VBX (n=9, 24.3%). Mean implantation time was 198.9 ± 90 minutes. Technical success was achieved in all but one case (n=17, 94%), with no 30 day mortality, no reinterventions, and 100% target vessel patency at a median follow-up of 10 months. Three patients (16.7%) died of non aortic-related causes. One residual type IA endoleak was adverted in computed tomography scan controls and was left untreated according to patient's decision.

CONCLUSION

PMEG utilizing the Medtronic Endurant endograft, supported by bidimensional templates and 3D-printed confirmation models, provided safe and effective short-term outcomes for complex, non-deferrable AAA repair. Long-term data and a prospective study on PMEG with a standardized protocol would allow for evidence to arise on this technique, facilitating adequate comparisons with custom-made and off-the-shelf devices.

CLINICAL IMPACT

This short series highlights the initial outcomes of physician-modified endografts (PMEG) using the Medtronic Endurant platform. Dedicated 2D templates for all Endurant sizes are provided as supplementary material, offering valuable assistance to practitioners in the vascular community. A standardized modification protocol, based on these templates along with the double-check of a sterile 3D-printed model, has allowed to achieve satisfactory short term outcomes. These outcomes are comparable to those of custom-made devices, even in scenarios requiring non-deferrable repairs and involving challenging anatomic constraints, such as type 1A endoleaks.

Long-Term Outcomes of Endovascular Aortic Repair with Parallel Chimney or Periscope Stent Grafts for Ruptured Complex Abdominal Aortic Aneurysms

Background: The parallel stent graft endovascular aortic repair (PGEVAR) technique is an off-the-shelf option used for elective complex abdominal aortic aneurysm repair with acceptable outcome results, as reported so far. The PGEVAR technique, using chimney or periscope parallel grafts, can also be used for patients with ruptured complex abdominal aortic aneurysms. However, only few data about the mid- to long-term outcomes are available. Methods: Data from patients treated between August 2009 and July 2023 with the PGEVAR technique for ruptured complex abdominal aortic aneurysms were analyzed. The endpoints of this study were primary and secondary technical success, perioperative mortality, rate of proximal type 1a (gutter) endoleaks (T1aEL), and overall and aneurysm-related survival. Secondary endpoints were major adverse events, durability of parallel grafts, and factors associated with overall survival. Results: Twenty patients (mean age: 77 ± 9 y; 18 male) with ruptured complex abdominal aortic aneurysm were treated, receiving PGEVAR for ruptured juxtarenal (n = 11), suprarenal (n = 7), or distal thoracoabdominal Crawford IV aortic aneurysms (n = 2) with a mean diameter of 82 ± 18 mm (range 59-120). The patients had PGEVAR with implantation of 39 parallel grafts (1.95 PGs per patient; 23 chimney and 16 periscope) for revascularization of the celiac artery (n = 3), superior mesenteric artery (n = 9), and renal arteries (n = 27). Three patients had delayed PG implantation within 10 days. Primary technical success was 15/20 (75%) with five patients having an early proximal T1aEL, three of them having successful reintervention (secondary success rate: 18/20; 90%), with no persistent bleeding. Two patients had late T1aELs. The presence of an early T1aEL was related to the number of PGs (≥2) implanted (p = 0.038) or insufficient aortic SG oversizing (p = 0.038). In-hospital mortality was 1/20 (5%). Perioperative mortality up to 32 days was 3/20 (15%), with two further late aneurysm-related deaths and eight late aneurysm-unrelated deaths (overall mortality 13/20; 65%) during follow-up (median 34 months; range 1-115). Major adverse events were observed in 11 (55%) patients. Secondary parallel stent graft patency at 1 and 3 years was 97.4 and 94.1%. During follow-up, aneurysm sac behavior was determined in 19 patients, which showed diameter progression (n = 3), stable aneurysm disease (n = 3), and aneurysm diameter regression in 13 (68.4%) patients. Overall survival was 75% after 1 year, and 53% and 22% after 3 and 5 years. Factors associated with overall long-term survival were age < 80 years (p = 0.037), juxtarenal aneurysms (p = 0.023), the absence of major adverse events (p = 0.025), and aneurysm sac regression (p = 0.003). Conclusions: Treatment of ruptured complex abdominal aortic aneurysm with the PGEVAR technique is associated with acceptable perioperative and long-term outcomes with high PG patency rates. Early proximal T1aELs are observed with a relevant frequency, requiring early reintervention with successful sealing of most relevant endoleaks. To note, limitation of the number of parallel stent grafts implanted at the proximal aortic sealing sites, sufficient PG sealing length, and adequate main aortic SG oversizing are most relevant to avoid T1a (gutter) ELs. The selection of juxtarenal aortic aneurysms and evidence for aneurysm sac diameter regression after PGEVAR had a prognostic impact.

Complex abdominal aortic aneurysms: a review of radiological and clinical assessment, endovascular interventions, and current evidence of management outcomes

Endovascular aortic aneurysm repair (EVAR) is an established approach to treating abdominal aortic aneurysms, however, challenges arise when the aneurysm involves visceral branches with insufficient normal segment of the aorta to provide aneurysm seal without excluding those vessels. To overcome this, a range of technological developments and solutions have been proposed including fenestrated, branched, physician-modified stents, and chimney techniques. Understanding the currently available evidence for each option is essential to select the most suitable procedure for each patient. Overall, the evidence for fenestrated endovascular repair is the most comprehensive of these techniques and shows an early post-operative advantage over open surgical repair (OSR) but with a catch-up mortality in the mid-term period. In this review, we will describe these endovascular options, pre- and post-procedure radiological assessment and current evidence of outcomes.