Extended use of endovascular aneurysm sealing: Chimneys for juxtarenal aneurysms

Urgent endovascular treatment of juxtarenal aneurysm using a parallel grafts technique

Abdominal aortic aneurysms can constitute a therapeutic challenge in several anatomical scenarios, making endovascular treatment more complex. A juxtarenal abdominal aortic aneurysm (JR-AAA) is defined by the absence of a proximal landing zone in the infrarenal segment and, therefore, techniques must be used to obtain an adequate neck for fixing the endoprostheses without provoking occlusion of renal arteries and visceral branches. The parallel grafts technique, physician-modified stent-graft, industry customized endoprostheses, and off-the-shelf branched endoprosthesis are techniques used in abdominal aneurysms with inadequate proximal neck, but each technique has its indications, limitations, and risks. In this therapeutic challenge, we present a case of urgent endovascular treatment of a JR-AAA using a parallel grafts technique, with good medium-term results, and discuss the therapeutic options.

Short-term outcomes of endovascular aortic aneurysm repair with the new Braile Biomédica® total custom-made abdominal endograft: Experience from three Italian centers

INTRODUCTION

Since 2019, Braile Biomédica® introduced a novel custom-made abdominal endograft tailored to the aorta's anatomy, featuring sizing every 3 mm and a diameter change from 50 mm to 8 mm. This design permits uncovered fenestrations around a single Z stent, eliminating the need for bridging stents to visceral vessels. Utilizing triple stent technology, optimal neck fixation is ensured, enabling treatment of necks shorter than 2 mm, with three 360° fenestrations optimizing graft fixation. This paper aims to analyze the initial experience with this custom-made infrarenal graft for abdominal aorta aneurysm (AAA), concerning procedural success and post-procedural short-term outcomes.

RESULTS

Among 12 patients treated from May 2022 to January 2024, technical success was achieved in 91.7 %, with only one intra-procedural complication. Follow-up CT scans at 1-3 months revealed resolution of an intraoperative endoleak and two late complications: a late type III endoleak and right renal artery occlusion.

CONCLUSIONS

The recent experience with Braile Biomédica® custom-made abdominal endograft demonstrates promising outcomes, particularly in treating AAAs with challenging anatomical features.

[Endovascular aortic repair: the hostile aneurysm neck : Morphologic definition, impact on long-term outcome, and treatment options]

DEFINITION

A hostile neck is defined by various anatomical conditions that describe a morphology of the proximal aneurysmal neck of infrarenal aortic aneurysms that is unfavorable for endovascular treatment (endovascular aortic repair, EVAR): proximal landing zone length ≤ 15 mm, angulation of the aortic neck > 60°, conical aortic neck, diameter of the aortic neck > 32 mm, and circumferential calcification/thrombus.

EFFECTS ON OUTCOME

These morphological parameters are not only associated with a higher perioperative technical failure rate (primary type 1 endoleak) but also with poorer long-term results (secondary type 1 endoleak) and thus a higher reintervention rate in standard EVAR, so that standard EVAR should be reserved for a few exceptions in these cases.

TREATMENT OPTIONS

Due to the rapid development of endovascular techniques in the last decade, we now have a variety of endovascular options for aneurysms with hostile necks, for both elective treatment and emergency care, in addition to conventional open surgery, which is still the standard method in many cases and is currently undergoing a renaissance: fenestrated endovascular aortic repair (FEVAR) as the method of first choice in the elective setting, EVAR with chimneys (ChEVAR), endosuture aneurysm repair (ESAR). An important option is the conservative approach, which can be a reasonable choice if the patient's preference is taken into account and a careful risk-benefit assessment is performed.

Immediate outcome of endovascular treatment of ruptured juxtarenal aneurysm with parallel stents

Rupture of an abdominal aortic aneurysm is an event with a high mortality rate and treatment is a medical emergency. Endovascular treatment of these aneurysms has become established as a minimally invasive alternative to classical open surgery and is now the first-choice option. However, 20 to 50% of patients with abdominal aortic aneurysms do not have anatomy favorable for endovascular treatment because of a short aneurysm neck or because visceral branches are involved by the aneurysm. We report the case of a 70-year-old patient who underwent endovascular repair of a ruptured juxtarenal aneurysm with deployment of parallel stents in the renal arteries (in a chimney technique). Clinical data and details of the procedure are reported. Technical success was achieved and there were no postoperative complications.

Secondary Fill Minimizes Gutter Size in Chimney EVAS Configurations In Vitro

Purpose: To investigate in an in vitro model if secondary endobag filling can reduce gutter size during chimney endovascular aneurysm sealing (chEVAS). Materials and Methods: Nellix EVAS systems were deployed in 2 silicone juxtarenal aneurysm models with suprarenal aortic diameters of 19 and 24 mm. Four configurations were tested: EVAS with 6-mm balloon-expandable (BE) or self-expanding (SE) chimney grafts (CGs) in the renal branches of both models. Balloons were inflated simultaneously in the CGs and main endografts during primary and secondary endobag filling and polymer curing. Computed tomography (CT) was performed immediately after the primary and secondary fills. Cross-sectional lumen areas were measured on the CT images to calculate gutter volumes and percent change. CG compression was calculated as the reduction in lumen surface area measured perpendicular to the central lumen line. The largest gutter volume and highest compression were presented per CG configuration per model. Results: Secondary endobag filling reduced the largest gutter volumes from 99.4 to 73.1 mm³ (13.2% change) and 84.2 to 72.0 mm³ (27.6% change) in the BECG configurations and from 67.2 to 44.0 mm³ (34.5% change) and 92.7 to 82.3 mm³ (11.2% change) in the SECG configurations in the 19- and 24-mm models, respectively. Secondary endobag filling increased CG compression in 6 of 8 configurations. BECG compression changed by −0.2% and 5.4% and by −1.0% and 0.4% in the 19- and 24-mm models, respectively. SECG compression changed by 10.2% and 16.0% and by 7.2% and 7.3% in the 19- and 24-mm models, respectively. Conclusion: Secondary endobag filling reduced paragraft gutters; however, this technique did not obliterate them. Increased CG compression and prolonged renal ischemia time should be considered if secondary endobag filling is used.