Bilateral Endograft Limb Occlusion after Endovascular Aortic Repair: Predictive Factors of Occurrence

Predictive Factors for Iliac Limb Occlusions After Endovascular Abdominal Aneurysm Repair: Determined from Aortoiliac Anatomy, Endovascular Procedures, and Aneurysmal Remodeling

Purpose

Iliac limb occlusion (ILO) is a serious complication of endovascular abdominal aneurysm repair (EVAR). This study aimed to identify predictive factors for ILO derived from aortoiliac morphology, endovascular procedure-related parameters, and aneurysmal remodeling characteristics.

Patients and Methods

Patient demographics, pre-EVAR anatomical characteristics of the aneurysm, endovascular procedure details, and post-EVAR aneurysmal remodeling outcomes were analyzed and compared using univariate analysis. Statistically significant factors were subsequently subjected to Cox regression and Kaplan-Meier analyses.

Results

Between January 2013 and April 2022, 66 patients were included in this study. Fourteen patients presented with ILO and were compared with 52 control patients with patent endograft limb over at least 1-year of follow-up. The tortuosity indices of the common iliac artery (CIA) and endograft iliac limb to vessel oversizing were significantly larger in the ILO group than in the patent endograft limb group. The CIA index of tortuosity ≥1.08, and endograft iliac limb to vessel oversizing ≥18.8% were independent predictors for ILO. During the follow-up of all patients, the proximal aortic neck and CIA diameters increased, aneurysm sac diameter decreased, and aortic neck and aortic length increased. The aortoiliac length increased over time in patients with patent endograft limb but not in patients with ILO. A change in the lowest renal artery-left iliac bifurcation distance ≦0.07 mm increased the risk of ILO.

Conclusion

ILO is predisposed to occur when the CIA index of tortuosity ≥1.08 and endograft iliac limb to vessel oversizing ≥18.8% are present. Significant aortoiliac remodeling, including proximal aortic neck dilatation, neck straightening, aneurysmal sac regression, iliac artery enlargement, and aortic lengthening, occurs after EVAR. Aortoiliac elongation was observed in patients with patent endograft limb, but not in patients with ILO. ILO was associated with a change in the lowest renal artery-left iliac bifurcation from the postoperative measurements ≦ 0.07 mm.

Sequential Graft Limb Occlusion Following Endovascular Aneurysm Repair: A Case Report and Literature Review

Limb graft occlusion (LGO) is a common complication that can occur after endovascular aneurysm repair (EVAR). There are many factors that can contribute to LGO, including patient-related variables, device-related considerations, and factors associated with the procedural technique. Patients with LGO may exhibit no symptoms, have intermittent claudication, or suffer from acute limb ischemia. In this manuscript, we present a case of a 64-year-old male who experienced sequential LGOs after EVAR accompanied by a comprehensive review of the pertinent literature.

Impact of iliac access in elective and non-elective endovascular repair of abdominal aortic aneurysm

Endovascular aortic repair (EVAR) is nowadays the establishment treatment for patients with abdominal aortic aneurysm (AAA) both in elective and urgent setting. Despite the large applicability and satisfactory results, the presence of hostile iliac anatomy affects both technical and clinical success. This narrative review aimed to report the impact of iliac access and related adjunctive procedures in patients undergoing EVAR in elective and non-elective setting. Hostile iliac access can be defined in presence of narrowed, tortuous, calcified, or occluded iliac arteries. These iliac characteristics can be graded by the anatomic severity grade score to quantitatively assess anatomic complexity before undergoing treatment. Literature shows that iliac hostility has an impact on device navigability, insertion and perioperative and postoperative results. Overall, it has been correlated to higher rate of access issues, representing up to 30% of the first published EVAR experience. Recent innovations with low-profile endografts have reduced large-bore sheaths related issues. However, iliac-related complications still represent an issue, and several adjunctive endovascular and surgical strategies are nowadays available to overcome these complications during EVAR. In urgent settings iliac hostility can significantly impact on particular time sensitive procedures. Moreover, in case of severe hostility patients might be written off for EVAR repair might be inapplicable, exposing to higher mortality/morbidity risk in this urgent/emergent setting. In conclusion, an accurate anatomical evaluation of iliac arteries during preoperative planning, materials availability, and skilled preparation to face iliac-related issues are crucial to address these challenges.

Novel Strategies for the Hostile Iliac Artery during Endovascular Aortic Aneurysm Repair

Successful endovascular aneurysm repair can be achieved with favorable aortic and iliac arterial anatomies. However, patients with challenging iliac anatomy, such as stenotic, calcified, tortuous arteries, or concomitant iliac artery aneurysms, are commonly encountered. Such a hostile iliac anatomy increases the risk of intraprocedural complications and worsens long-term outcomes. This review addresses various technical options for treating patients with a hostile iliac anatomy, including innovative endovascular solutions, physician-modified endografts, and hybrid procedures. These considerations demonstrate the wide scope of therapies that may be offered to patients with an unfavorable iliac anatomy.

Factors Related to Limb Occlusion After Endovascular Abdominal Aortic Aneurysm Repair (EVAR)

BACKGROUND

Limb occlusion is a potentially serious consequence of endovascular abdominal aortic aneurysm (EVAR). This case-control study identifies factors that predispose to limb occlusion.

METHODS

A consecutive series of patients from 2 centers undergoing EVAR over an 11-year period 2007-2017 were identified retrospectively. Patient records were interrogated allowing collations of demographics, intraoperative and perioperative data and surveillance data. The preoperative computed tomography angiogram was analyzed to determine EVAR relevant anatomical data. The primary outcome was occlusion of the iliac limb of the implanted EVAR. Raw data are presented as percentages, with comparative data analyzed using Mann-Whitney U-test and binomial logistic regression.

RESULTS

A total of 787 patients (702 males; median age 78 years, range 53-94 years old) were analyzed. Fifty patients reached the primary outcome, resulting in an overall limb occlusion rate of 6.35%. Factors predictive of limb occlusion were oversizing by >10% native vessel diameter, with oversizing of >20% in 50% of those that occluded. External iliac artery landing zone (12/50 limb occlusions) 24% and postoperative kinking (5/50 limb occlusions) 10% were also more common in those that occluded. Fifty randomly selected controls with similar baseline characteristics were studied. Oversizing of the iliac endograft was found to be significantly greater in the limb occlusion group compared to the controls (P < 0.001) which remained significant on regression analysis. There was no correlation with iliac tortuosity. The Cook stent graft had a 9% limb occlusion rate across sites. Medtronic and Vascutek endografts had 2.4% and 2.5% limb occlusion rates respectively.

CONCLUSIONS

Oversizing of iliac limbs by >20% could be a contributing factor to limb occlusion after EVAR and judicious oversizing should be used.

Aneurysm Sac Shrinkage After EVAR Can Lead to Complications: A Case Report of Complete Endograft Thrombosis Due to Kinking

BACKGROUND

Bilateral limb occlusion after endovascular repair of abdominal aortic aneurysms (EVAR) is an uncommon entity. The relationship between graft kinking and unilateral limb occlusion is widely described in the literature. Our aim is to report a case of complete endograft thrombosis due to bilateral limb kinking secondary to aneurysm sac shrinkage, treated by endovascular means.

CASE REPORT

A 67 year-old male with history of EVAR with an Incraft® endograft (Cordis, Bridgewater, NJ, USA) four years before, presented at the emergency department with disabling claudication of the right lower extremity and a better tolerated 10-month left extremity claudication. Complete endograft thrombosis with bilateral limb kinking and a remarkable reduction of the aneurysm sac was observed in the computed tomography angiography. An endovascular repair was performed, through bilateral open femoral access and with angiographic control through percutaneous left brachial access. Bilateral recanalization was achieved and the endograft was re-lined with two 10x150 mm Viabahn (WL Gore & Ass., Flagstaff, AZ, USA). Both sides were extended with a 11 × 50 mm Viabahn (WL Gore & Ass., Flagstaff, AZ, USA). The final angiographic control showed bilateral patency with no residual stenosis and the patient recovered distal pulses. Follow-up showed complete patency and no complications at 17 months.

CONCLUSIONS

Bilateral limb occlusion is a rare complication with technically challenging treatment options. Aneurysm sac shrinkage can affect the endograft configuration, leading to limb distortion and occasionally to bilateral limb occlusion after EVAR. Special attention should be put on imaging follow-up to detect these complications before occlusion occurs.

External iliac artery extension causes greater aneurysm sac regression than the bell-bottom technique or iliac branch endoprosthesis for repair of concomitant infrarenal aortic and iliac artery aneurysm

OBJECTIVE

Aneurysmal extension of abdominal aortic aneurysms (AAAs) to the common iliac artery (CIA) presents a technical challenge to successful endovascular abdominal aortic aneurysm repair (EVAR). In the present study, we compared sac shrinkage and perioperative outcomes after the bell-bottom technique (BBT), internal iliac artery embolization and external iliac artery extension (EIE), and iliac branch endoprosthesis (IBE).

METHODS

Using the Vascular Quality Initiative database, a retrospective analysis was conducted for patients who had undergone EVAR from 2013 to 2019. The demographic, anatomic, and perioperative data were analyzed. All patients with a proximal aortic neck length <10 mm and aortic graft diameter >32 mm were excluded from the analysis. The patients were subdivided into four groups according to the distal limb strategy: group 1, control group with a bilateral common iliac artery limb <20 mm; group 2, BBT with either a unilateral or bilateral limb >20 mm; group 3, EIE technique; and group 4, IBE. The primary endpoint was the maximal change in the aortic diameter during follow-up. The secondary endpoints included postoperative complications and the rate of endoleak.

RESULTS

The records for 14,455 patients who had undergone EVAR were queried and 5788 met the anatomic criteria. The average age was 73 years, and 86.3% were men. The maximal change in the aortic diameter in the control, BBT, IBE, and EIE groups was -7.2 mm, -6.1 mm, -4.6 mm, and -6.8 mm, respectively (P = .06). The differences were not statistically significant on univariate analysis at an average follow-up of 405 days. However, on multivariable analysis (P = .01), compared with the control group, the BBT and IBE groups were 18.4% (odds ratio [OR], 0.816; 95% confidence interval [CI], 0.68-0.98) and 48.0% (OR, 0.52; 95% CI, 0.33-0.82) less likely to experience aneurysmal shrinkage, respectively. In contrast, the EIE group showed no significant difference in shrinkage compared with that in the control group. Multivariable analysis of the groups also revealed that compared directly with the BBT group, the EIE group was 69.5% more likely to have experienced shrinkage in the aortic aneurysmal diameter (OR, 1.70; 95% CI, 1.05-2.75). The BBT and IBE groups had a significantly higher rate of type II endoleaks (17.63% and 16.95%, respectively; P = .03). The EIE group had a higher rate of type Ib endoleaks (1.9%) compared with the BBT (1.1%), IBE (1.7%), and control (0.3%) groups (P = .01). No differences were found between the groups in terms of postoperative myocardial infarction (P = .47) or respiratory (P = .61) or intestinal (P = .71) complications. However, the rates of limb complications and reoperation were higher in the EIE group.

CONCLUSIONS

The present study revealed that the EIE technique was more likely to demonstrate shrinkage in the aortic aneurysmal diameter than were the BBT and IBE groups compared with the control group on multivariable analysis. The EIE technique was also more likely to result in aneurysmal sac shrinkage than was the BBT group, albeit with greater rates of limb-related complications.

Limb Graft Occlusion Following Endovascular Aneurysm Repair for Infrarenal Abdominal Aortic Aneurysm with the Zenith Alpha, Excluder, and Endurant Devices: a Multicentre Cohort Study

OBJECTIVE

Limb graft occlusion (LGO) is a serious complication after endovascular aneurysm repair (EVAR) and while device development enables treatment of increasingly complex aortic anatomy, little is known about how endograft type affects the risk of occlusion. This observational study aimed to explore the incidence of LGO after EVAR for three major endograft systems.

METHODS

All patients with standard EVAR as the primary intervention for infrarenal abdominal aortic aneurysm (AAA), between January 2012 and December 2018, at five Swedish vascular surgery centres, were included in this multicentre retrospective cohort study. LGO was defined as a total limb occlusion regardless of symptoms, or a treated significant stenosis. A nested case control (NCC) design with incidence density sampling of 1:3 was used for analysis of potential per-operative and morphological risk factors. Conditional logistic regression was used to estimate multivariable odds ratios (OR) with 95% confidence intervals (CI) RESULTS: A total of 924 patients were included. The majority were male (84%), the mean age was 76 years (± 7.5 SD), and median AAA diameter was 59 mm (IQR 55, 67). Patients were treated with Zenith Alpha (n = 315, ZISL limbs), Excluder (n = 152, PLC/PXC limbs), and Endurant (n = 457, ETLW/ ETEW limbs). During median follow up of 37 months (IQR 21, 62), 55 occlusions occurred (5.9%); 39 with Zenith Alpha (12.4%), one with Excluder (0.7%), and 15 with Endurant (3.3%). In the NCC analysis, the Zenith Alpha device (OR 5.31, 95% CI 1.97 - 14.3), external iliac artery (EIA) landing (OR 5.91, 95% CI 1.30 - 26.7), and EIA diameter < 10 mm (OR 4.99, 95% CI 1.46 - 16.9) were associated with an increased risk of LGO.

CONCLUSION

Endograft device type is an independent risk factor for LGO after EVAR. Specifically, the Zenith Alpha demonstrated an increased risk of LGO compared with the Endurant and Excluder devices. In addition, a narrow EIA and landing zone in EIA are also risk factors for LGO.

Ten-year single center experience in elective standard endovascular abdominal aortic aneurysm repair

BACKGROUND

Endovascular aneurysm repair (EVAR) has become the treatment of choice for abdominal aortic aneurysm (AAA), demonstrating excellent early outcomes. However, EVAR durability has been questioned in the long-term period. The aim of this study was to assess EVAR outcomes in terms of survival and freedom from re-intervention during a long-term period.

METHODS

All consecutive patients being treated, with elective standard EVAR, in a single tertiary center, were included between 2008 and 2018. Outcomes were defined as survival and freedom from re-intervention and were reported using Kaplan-Meyer lifetables. In subgroup analyses, sex, age (threshold at 65 and 80 years), neck diameter>28mm and type of fixation were also analyzed. Type of re-intervention and endoleak type I (ETIa) were also reported.

RESULTS

Five hundred and eight patients (94% males, mean age 72±7.3, mean AAA diameter 59±9mm) were included. The median follow-up was 3 years (range 0-10 years). The survival rate was 92.8% (SE 1.5%), 76.5% (SE 3.1%) and 41.6% (SE 6%), at 2, 5 and 10 years of follow-up, respectively. In total, 78 patients died; 8 deaths (8/75, 10%) were aneurysm related. In multivariate regression analysis, age (CI. 1.02-1.14; p=0.006) and ever tobacco use (CI. 1.02-6.12, P=0.045) were associated with the long-term mortality. Freedom from re-intervention was 96% (SE 1.1%), 93% (SE 1.8%), 85.5% (SE 5%) at 2, 5 and 9 years of follow-up. Limb occlusion was a common complication (n/n; 30% of re-intervention), particularly within the first 2 postoperative years. Six patients presented with rupture and were treated with open conversion. EVAR cases with supra-renal fixation graft presented lower rates of ETIa (CI. 76-87.27, P<0.001).

CONCLUSIONS

Elective standard EVAR is associated with good long-term survival showing low aneurysm-related mortality. Common risk factors such as advanced age and smoking are associated to higher mortality. The procedure presents low re-intervention rates, while limb occlusion is a complication presented within the first 2 postoperative years.

Results of adjunctive stenting with high-radial force stents to prevent or treat limb occlusion after EVAR

BACKGROUND

The aim of this study was to report the results of a multicenter experience on the use of adjunctive stents deployed inside abdominal aortic endografts with the purpose to prevent or treat limb occlusion after endovascular aneurysm repair (EVAR).

METHODS

Between 2010 and 2018, there were 35 patients with aorto-iliac aneurysm presenting one or more risk factors for endograft limb occlusion (narrow aortic bifurcation and/or stenotic, highly angulated or occluded iliac arteries), who were treated with standard bifurcated stent graft reinforced by the means of a single model of balloon-expandable platinum/iridium bare stent (CP Stent; NuMED, Inc., Hopkinton, NY, USA). Technical success, mortality, limb patency and reintervention rate during follow-up were the main endpoints assessed.

RESULTS

Technical success was 100%. No patients died perioperatively and no major complication was registered. During a mean follow-up of 48 months (range 1-87), neither aortic-related death nor secondary intervention was registered. At a mean follow-up imaging of 39.4 months (range 1-81) no endograft limb lost its patency.

CONCLUSIONS

The use of high-radial force balloon-expandable stents deployed inside bifurcated endografts to prevent or treat limb occlusion is a safe and effective adjunctive procedure, with outstanding long-term outcomes in terms of patency and reinterventions.

Preservation of internal iliac artery flow during endovascular aortic aneurysm repair in a patient with bilateral absence of common iliac artery

Bilateral absence of the common iliac artery is an extremely rare congenital vascular malformation in which the distal aorta divides directly into two external iliac arteries and two internal iliac arteries. In the case of the presence of this vascular malformation in association with an aortic aneurysm, preservation of the internal iliac artery flow during endovascular aortic repair represents a technical challenge. We have reported a case in which the bilateral absence of the common iliac artery associated with an infrarenal abdominal aortic aneurysm was successfully treated by endovascular aortic repair using commercially available iliac branched devices to maintain pelvic perfusion.

Symptomatic Aortic Endograft Occlusion in a 70-year-old Male

Case Presentation

A 70-year-old male with prior aorta endovascular aneurysm repair presented with progressive lower extremity weakness over the course of several hours. There was noted loss of palpable bilateral femoral pulses in the emergency department. Computed tomography angiography revealed a kinked and occluded aortic endograft. He subsequently underwent successful axillobifemoral bypass revascularization.

Discussion

Kinking of endograft limbs and occlusion has been reported in a small percentage of patients. Bilateral leg ischemia due to aortic endograft occlusion is rare.

Long-Term Outcomes of Percutaneous Stenting of Aortic Endograft Limb Occlusion

INTRODUCTION

To investigate the safety and efficacy of percutaneous stenting for the management of chronic ischemia caused by endograft limb occlusion following endovascular aortic aneurysm repair (EVAR).

METHODS

This is a retrospective, single-center study investigating all patients who underwent percutaneous endovascular covered or bare metal stent placement for the management of intermittent claudication (IC) or critical limb ischemia following EVAR limb occlusion, between January 2010 and October 2017. Cases suffering from acute limb ischemia were treated surgically and were excluded from the analysis. Primary outcome measures were technical success and symptoms-free interval. Secondary outcome measures included clinically driven target-lesion reintervention (TLR)-free survival, primary patency, and complication rates.

RESULTS

Of 29 limb occlusions, 11 limbs (11 patients; 100% male; mean age: 71.6 ± 6.9 years) were treated percutaneously and were included in the study. The majority suffered from IC (10/11; 90.9%) with a single case of rest pain. Technical success was obtained in 10 patients (90%). No major complications occurred. Mean follow-up time was 37.6 ± 25.7 months. Stent grafts were mainly used, while and in 2 cases (18.18%), only nitinol bare stents were deployed. According to Kaplan-Meier analysis, both symptoms-free interval and primary patency were 83.33% in up to 5 years follow-up. TLR-free survival was 100% at 5 years, as 2 cases of claudication relapse were managed conservatively.

CONCLUSIONS

Percutaneous stenting for the management chronic ischemia due to EVAR limb occlusion is feasible and safe, with satisfactory long-term outcomes. Careful patient selection warrants clinical success.

Endovascular Aneurysm Sealing of a Collapsed and Thrombosed Aortic Stent-Graft With Renovisceral Chimney Stent-Grafts

PURPOSE

To report the use of the Nellix endovascular aneurysm sealing (EVAS) system in the management of proximal stent-graft collapse associated with thrombosis following endovascular aneurysm repair (EVAR).

CASE REPORT

A 76-year-old man was admitted for proximal collapse of an aortic extension following bifurcated AFX stent-graft implantation associated with chimney grafts in both renal arteries and the superior mesenteric artery 1 month prior. Imaging identified thrombosis of the aortic stent-graft and the iliac limbs. A Nellix EVAS was placed into the AFX stent-graft to recanalize the aneurysm lumen and address the aortic thrombosis. There was no endoleak, and the renovisceral chimney stent-grafts remained patent over a follow-up of 25 months.

CONCLUSION

While further studies are required to generalize its use, EVAS appears to be feasible in the management of aortic stent-graft collapse.