Modified Sandwich-graft Technique Employing Aorfix and Viabahn Stent-grafts to Preserve Hypogastric Flow in Cases of Complex Aortoiliac and Isolated Common Iliac Artery Aneurysms Including the Internal Iliac Artery Ostium

Endovascular repair of bilateral isolated common iliac artery aneurysms with unsuitable anatomy utilizing an aortic bifurcated unibody endograft and modified sandwich technique to preserve pelvic blood flow: a case series

Bilateral isolated common iliac artery aneurysms (CIAAs) are rare, and endovascular repair of CIAAs has emerged as an alternative to traditional open surgical repair. The primary goal of therapy is to exclude the aneurysm sac while maintaining perfusion of at least one internal iliac artery (IIA) to prevent pelvic ischemia. Although the iliac branch device (IBD) has improved the feasibility of preserving the IIA, its applicability is limited to a specific subset of aneurysm anatomy. We present a case series of three patients with bilateral isolated CIAAs in whom preoperative CT scans revealed an absence of a landing zone, the diameter of proximal CIA diameter was less than 13.0 mm, and normal diameter of the nonaneurysmal infrarenal aorta, making it challenging to use an IBD alone or a standard bifurcated aortic endograft to provide a proximal landing zone for iliac artery stenting. To overcome the small diameter of the infrarenal aorta, we implanted an aortic bifurcated unibody endograft. Then, we utilized a balloon-expandable covered stent-graft with overdilation as a modified sandwich technique to create an "eye of the tiger" configuration to prevent gutter leakage. The final angiography performed during the procedure revealed successful exclusion of the aneurysms, with blood flow to the right IIA and no type III endoleak. During the postoperative follow-up period, no patients exhibited symptoms associated with pelvic ischemia. There were no endoleaks or sac expansions on the two-year follow-up CT scans, and all external and internal iliac graft limbs were patent. This study demonstrated that a combination of an aortic bifurcated unibody endograft and a modified sandwich technique can effectively treat bilateral isolated CIAAs with certain anatomical constraints.

Novel Surgeon-Modified Fenestrated Iliac Stent Graft

PURPOSE

We describe the feasibility and early results of a novel endovascular approach with a surgeon-modified fenestrated iliac stent graft to preserve pelvic perfusion in patients with iliac aneurysms not suitable for iliac branch devices (IBDs).

TECHNIQUE

Seven high-risk patients, median age 76 years (range 63-83), with a complex aortoiliac anatomy with contraindications for commercially available IBDs were treated with a novel surgeon-modified fenestrated iliac stent graft between August 2020 and November 2021. The modified device was built using an iliac limb stent graft (Endurant II Stent Graft; Medtronic), which was partially deployed, surgically fenestrated with a scalpel, reinforced, re-sheathed, and inserted via femoral access. The internal iliac artery was cannulated and bridged with a covered stent. Technical success rate was 100%. After a median follow-up period of 10 months, there was 1 type II endoleak and no migrations, stent fractures, or loss of device integrity. One iliac limb occlusion occurred after 7 months, which needed a secondary endovascular intervention, restoring patency.

CONCLUSION

Surgeon-modified fenestrated iliac stent graft is feasible and might be used as an alternative in patients with a complex iliac anatomy not suitable to commercially available IBDs. Long-term follow-up is needed to evaluate stent graft patency and potential complications.

CLINICAL IMPACT

Surgeon modified fenetrated iliac stent grafts might be a promising alternative to iliac branch devices, extending endovascular solutions to a broader patient population with complex aorto-iliac anatomies preserving antegrade internal iliac artery perfusion. It is possible to treat small iliac bifurcations and large angulations of the iliac bifurcation safely and there is no need for a contralateral or upper-extremity access.

Midterm Results of a Surgeon-Modified Device to Preserve the Flow of the Internal Iliac Artery During Endovascular Repair of Aneurysm: Single-Center Experiences

BACKGROUND

During endovascular aneurysm repair (EVAR), commercial iliac branch devices (IBDs) have become an inescapable alternative for preserving antegrade internal iliac artery (IIA) blood flow. Due to the different morphological features of aneurysms, commercial IBDs may not be suitable for all patients. Reported experience with the implantation of the new surgeon-modified IBD (sm IBD) is limited. This investigation describes the indications, efficacy, and safety of the sm IBD.

METHODS

Data from consecutive elective implantations of IBDs in patients between March 2011 and May 2021 in a single center were incorporated. The sm IBDs were indicated in patients with common iliac artery aneurysms (CIAAs) and with a challenging anatomy and in those patients with or without abdominal aortic aneurysm (AAA).

RESULTS

Fifteen patients (15 male, mean age 67.6 ± 7.9 years) were included. Fifteen sm IBDs were implanted in 1 procedure (100%). Fourteen (93.3%) patients had simultaneous endovascular aneurysm repair (EVAR) and 1 (6.7%) patient previously had a bilateral CIAAs repair by EVAR. The mean common iliac artery (CIA) diameter was 36.6 ± 12.5 mm. Technical success was obtained in all patients (100%). The median operation time was 189.7 ± 78.6 min, with a median fluoroscopy time of 45.3 ± 15.9 min. Axillary artery access was used in 11 (73.3%) procedures. The mean total hospital stay was 5.6 ± 2.8 days, and the postoperative follow-up was 35.4 months (range 2-120). The estimated IIA bridge stent patency at 1 year after operation was 100% and 85.7% ± 13.2% 5 years postoperatively. One (6.7%) IIA branch was occluded, and this patient remained asymptomatic. One patient (6.7%) needed reintervention, and another (6.7%) patient had type II leakage, which is currently under close surveillance.

CONCLUSIONS

Using an IBD to maintain the pelvic blood flow is an effective and feasible intravascular technique, especially for patients with an abnormal iliac artery anatomy. This novel technique has similar midterm procedural success rate compared to the use of commercial IBDs. Therefore, these devices are more suitable for patients with certain anatomic challenges and can be used as an alternative treatment.

Endovascular Repair for Giant Right Subclavian Artery Aneurysm With Gore Viabahn and Pull-Through Procedure: A Case Report

Background

Giant true subclavian artery aneurysms (SAAs) (>5 cm) are rare. Technical and anatomical considerations complicate the endovascular treatment of SAAs and pose some challenges. Here, we present a giant right SAA that was successfully excluded using stent grafts with the pull-through technique after two interventional steps and discuss the pull-through technique details as well as the lessons to be learned from this case.

Methods

A 50-year-old man presented at our department complaining of dyspnea and hoarseness. Computed tomography angiography (CTA) showed a giant right SAA with partial intraluminal thrombus and severe angulated aneurysm necks originating from the proximal right subclavian artery, approximately 70 × 71 mm in size.

Outcomes

An 8 × 100-mm Gore Viabahn was selected to exclude the SAA. A decision was made to stabilize the wire tension using the pull-through technique. Final angiography showed that the SAA was essentially excluded, and slight endoleak was observed. At 6 months, imaging showed that the aneurysm was not obviously shrinking, there was still an endoleak and stent graft dislodgement was observed. Angiography confirmed a type Ia endoleak, which was managed by the placement of a 10 × 50-mm Gore Viabahn, again with the assistance of the pull-through technique. At the 25-month follow-up, CTA showed that the SAA was satisfactorily excluded, with no endoleak, and the SAA was reduced in size.

Conclusions

Endovascular treatment of SAAs is a safe, reliable and minimally invasive approach. The pull-through technique may improve wire tension and device stabilization. Additionally, size selection and positioning should be reappraised under a severely angulated aneurysm neck.

Similar Midterm Clinical Outcomes and Aortic Remodeling in Bifurcated and Straight Aortic Stent Grafts Used to Treat Isolated Abdominal Aortic Dissection

PURPOSE

The optimal treatment for isolated abdominal aortic dissection (IAAD) is currently unknown. We compared the effects of straight and bifurcated aortic stent grafts on postoperative aortic remodeling in patients with IAAD.

MATERIALS AND METHODS

From February 2012 to December 2019, 57 patients with IAAD were treated using endovascular methods, including either a bifurcated or a straight aortic stent graft. The clinical features, risk factors, computed tomography angiograms, midterm follow-up results, and aortic remodeling of these patients were reviewed and analyzed.

RESULTS

In total, 44 (77%) patients were treated with a bifurcated graft and 13 (23%) patients were treated with a straight graft. Patients treated with straight grafts had fewer common iliac arteries involved (38% vs 73%, p=0.023), the dissection length was shorter (76.3 ± 40.0 vs 116.2 ± 56.7 mm, p=0.011), and the preoperative aortic diameter (26.0 ± 5.6 vs 35.2 ± 12.1 mm) and the false lumen diameter (13.1 ± 5.2 vs 21.2 ± 11.3 mm) were smaller. During the procedure, there were 3 (5.3%) type I endoleaks, 1 (1.8%) surgical conversion and 1 (1.8%) partial renal artery coverage without perioperative mortality. Patients with straight grafts had shorter operative time (96.5 ± 24.4 vs 144.2 ± 49.0 minutes, p<0.0001). The median follow-up duration was 37.6 ± 21.0 (range = 3-89) months with 1 (1.8%) aortic-related death. Type A aortic dissection occurred in 1 (1.8%) patient. New descending aortic dissection occurred in 3 (5.3%) patients, and 1 patient advanced to type A aortic dissection 3 months later. Two (3.5%) patients had limb occlusion. There was no significant difference in aortic remodeling, survival, and freedom from all adverse events between the 2 treatment strategies.

CONCLUSIONS

Endovascular treatment provides a safe, minimally invasive treatment for IAAD in midterm follow-up. Compression of the true lumen at the aortic bifurcation is the main concern after treatment with a bifurcated graft. Straight grafts are an excellent alternative for some patients, with the benefit of reduced procedural time, effective aortic remodeling, and excellent clinical prognosis. More experience is needed to offer clear recommendations for making treatment decisions as well as determine long-term effectiveness and durability.

Endoluminal Management of Infra-renal Aortic and Aorto-iliac Aneurysms

This paper reviews the development of endovascular aneurysm repair (EVAR) of infra-renal aortic and iliac artery aneurysms and considers the current status and best treatment options. The vast majority of devices are bifurcated and exclude the aneurysm utilizing the same techniques for fixation and seal. The modern EVAR procedure is usually performed in a hybrid operating theatre, utilizing image fusion and other radiation-reducing techniques and using optimized procedural techniques, including percutaneous access. The best outcomes are achieved in patients whose anatomy is within device "instructions for use", but these are most commonly breached due to "hostile" neck anatomy. Endovascular options for these cases include the use of fenestrated endografts, chimney grafts and endoanchors. Concomitant iliac artery aneurysms often occur with abdominal aortic aneurysms, and endovascular options include limb extensions with internal iliac embolization as well as iliac branch devices. The durability of EVAR has recently been called into question by long-term results from early EVAR randomized trial. Findings such as infra-renal neck dilatation and aneurysm sac expansion are relatively common and associated with adverse outcomes. This durability concern mandates regular and long-term imaging and clinical surveillance. It also indicates that EVAR technology is not fully evolved with a need for further development to improve patient applicability and long-term durability.

Endovascular treatment of iliac aneurysmal disease with internal iliac artery preservation: a review of two different approaches

INTRODUCTION

The feasibility of endovascular aneurysm repair (EVAR) is often challenged by the concurrent presence of common iliac artery aneurysms, which prevent the attainment of a successful distal sealing. The present review aims to portray the safety and efficacy of two internal iliac artery (IIA) preservation strategies in the endovascular treatment of aortoiliac aneurysms: the iliac branch extension device (IBED) and the parallel graft - "sandwich" technique (PG-ST).

EVIDENCE ACQUISITION

A comprehensive literature review was conducted to identify publications on endovascular treatment of iliac aneurysmal disease using IBED or PG-ST. Primary endpoints were freedom from endoleak, IIA branch occlusion and secondary interventions.

EVIDENCE SYNTHESIS

Twenty-eight studies were selected for analysis describing a total of 1316 patients, 1169 in the IBED group and 147 in the PG-ST group. The technical success rates were akin for IBED and PG-ST (83.9-100% versus 81.3-100%). The defined primary endpoints were reported by fourteen articles. Freedom from endoleak, IIA branch occlusion and reintervention, at 6 months, were as follows: 82-100% versus 86%, 90-94% versus 88%, and 90-98% versus 87%, respectively for IBED and PG-ST. Later outcomes were only recorded in the IBED group, and freedom from endoleak, IIA branch occlusion and reintervention, at 9 years, were 83%, 81-90%, and 64-75%, respectively.

CONCLUSIONS

Both IBED and PG-ST have proven to be safe and valid approaches. However, while IBED has established as a durable procedure, mid-term data lacks on PGs performance and further studies are required to attest durability of the latter procedure.

Selection of Stents by Calculation of Arterial Cross-sectional Area in Modified Sandwich Technique for Complex Aortoiliac Arterial Lesions

BACKGROUND

We prospectively evaluated the modified sandwich technique for treatment of complex aortoiliac arterial lesions using commercial stent grafts selected according to the arterial cross-sectional area. The primary outcomes were technical feasibility and mid-term follow-up results.

METHODS

We prospectively enrolled 13 patients (mean age 63.85 ± 6.12 years) with aortoiliac arterial lesions (5 infrarenal abdominal aortic dissections, 1 lower abdominal aortic occlusion, 5 iliac artery aneurysms, 1 external iliac arterial pseudoaneurysm, and 1 type IB endoleak following endovascular aneurysm repair) for endovascular repair with the modified sandwich technique. All lesions were complex and unsuitable for routine endovascular treatment. The bifurcated stent-graft diameters were determined by calculating the arterial cross-sectional area. Success and complication rates were recorded. Patients were followed for 20.69 ± 6.51 (range 6-31) months and stent patency determined by contrast-enhanced ultrasound and computed tomography 1, 3, and 6 months post-operatively and every 12 months thereafter.

RESULTS

The initial technical success rate was 100%, and no surgical complications occurred. The primary patency of the stent grafts was 100% during follow-up. Post-procedural type I "gutter" endoleaks occurred in 4 patients (30.8%) after 1 month. At 3 months, the endoleaks in 3 of the 4 patients had disappeared without treatment, and the remaining endoleak resolved after coil embolization.

CONCLUSIONS

The sandwich technique is a safe and effective therapy for complex aortoiliac arterial lesions. Stent-graft sizes based on the arterial cross-sectional area can ensure technical success and reduce the rate of "gutter" endoleaks.

Parallel-Stenting Technique in a Sandwich Configuration for Hypogastric Artery Preservation during Endovascular Aneurysm Repair: An In Vitro Study

BACKGROUND

The aim of the study was to identify the best conditions in iliac sandwich procedure for hypogastric artery preservation during endovascular aneurysm repair, testing different devices, different oversizing (OS) degrees as well as different methods to measure it.

METHODS

Four external iliac devices (16-mm Endurant and 12-mm Aorfix limb extensions; 11- and 13-mm Viabahn endografts) were tested with 2 distinct internal iliac stent grafts (8-mm Advanta V12 and 8-mm Viabahn) inside different proximal silicon iliac limb models (10, 12, 14, 16, and 18 mm), simulating an iliac sandwich procedure for hypogastric preservation. After remodeling all devices in a saline bath at 37°C, the combinations were computed tomography scanned. Gutter size, parallel-stent compression, and inadequate parallel-stent deployment or infolding were recorded. Oversizing between both parallel stents and the iliac limb models were examined in terms of added diameter, perimeter, and area being additionally compared.

RESULTS

All three sizing methods (diameter, perimeter, and area) were highly correlated (diameter OS to perimeter and area OS correlation coefficient 0.998 and 0.997, respectively, P < 0.001 for both); thus, diameter OS was used for further comparisons. Increasing diameter OS (< 30%, 30-55%, 55-75%, and > 75%) showed a significant tendency toward smaller gutters (38.9, 12.2, 5.4, and 2.6 mm², respectively, P < 0.001) but also increasing parallel-stent compression (13.5%, 28.9%, 43.9%, and 55.1%, P < 0.001) and infolding (0%, 0%, 38%, and 60%, P < 0.001). There were no significant differences between the analyzed devices.

CONCLUSIONS

In iliac sandwich procedures, better apposition is usually achieved when using 30-55% diameter OS; higher OS is related to smaller gutters but higher rates of malpositioning and parallel-stent compression. No clear recommendations in material selection can be performed. All sizing methods are highly correlated and predictable.