Double-Barrel Technique With Reversed Gore Excluder Stent Graft Limb for Common Iliac Aneurysm Exclusion in a Patient With Prior Aortic Surgical Repair.

Surgical repair of a common iliac artery aneurysm (CIA) after previous open aortic reconstruction is associated with significant morbidity and mortality. Endovascular repair is considered less invasive than surgery. However, if preservation of the internal iliac artery (IIA) is required, the applicability of endovascular techniques may represent a challenge and a limitation to the use of standard aortic endografts or iliac branch devices. In these cases, the off-label use of endovascular devices may be an effective alternative. Herein, we report a successful hybrid approach to treat CIA using a reversed iliac limb endograft coupled with a double-barrel technique with femoro-femoral crossover bypass in a patient who had previously undergone open aortic reconstruction.

Outcomes and Economic Impact of Hypogastric Artery Management During Elective Endovascular Aortic Repair for Aorto-Iliac Aneurysms.

BACKGROUND: To analyze clinical outcomes and perform a macro-costing evaluation of endovascular aortic repair (EVAR) for aorto-iliac aneurysms. METHODS: This is a retrospective, financially unsupported, physician-initiated observational cohort study. Patients with iliac artery involvement treated with EVAR between January 1st, 2014 and December 31st, 2021 were identified. Inclusion criteria were intact aneurysm, elective EVAR with at least 1 hypogastric artery (HA) treatment, use of bifurcated endograft (EG), and at least 6 months of follow-up. Primary outcomes of interest were overall survival, freedom from aneurysm-related mortality (ARM), freedom from EVAR-related reintervention, and overall EVAR(procedure)-related costs. RESULTS: We studied 122 (9.1%) patients: 119 (97.5%) were male and 3 (2.5%) females. Median age of patients was 76 years (range, 68.75-81). Overall, 107 (87.7%) patients had both HAs preserved according to following strategy: 45 (36.9%) with flared limbs, 13 (10.6%) with bilateral branched device, and 49 (40.2%) with a combination of flared limb on 1 side and branched device on the contralateral side. Bilateral overstenting was performed in 15 (12.3%) patients. Estimated overall survival was not different between groups of EVAR (Log-rank, P = 0.561). There was only 1 (0.8%) ARM ascertained during the follow-up. Estimated freedom from EVAR-related reintervention was not different among groups (Log-rank, P = 0.464). During the follow-up, 9 (7.4%) patients developed buttock claudication (Society for Vascular Surgery (SVS) grade 1, n = 4, SVS grade 2, n = 5), more frequently in HA overstenting (hazard ratio (HR): 3.6; 95% confidence intervals (CIs): 0.96-13.5, P = 0.058). When all cots were included, branched EVAR still carried the highest burden (P = 0.001) in comparison with the mixed subgroup, the overstenting subgroup, and the flared limbs subgroup. CONCLUSIONS: Early mortality and pelvic ischemic syndromes rate were acceptably low in all techniques. Hypogastric artery preservation showed lower complication rate in comparison with HA overstenting which, however, appears to be safe an effective for option with similar overall costs for patients who are not candidates for HA preservation based on aortic anatomy.

Cryopreserved Arterial Allografts Versus Rifampin-Soaked Dacron for the Treatment of Infected Aortic and Iliac Aneurysms.

BACKGROUND: Infected aortic and iliac artery aneurysms are challenging to treat. Cryopreserved arterial allografts (CAAs) or rifampin-soaked Dacron (RSD) are standard options for in situ reconstruction. Our aim was to compare the safety and effectiveness of CAA versus RSD for these complex pathologies. METHODS: This is a retrospective review of infected iliac, abdominal, and thoracoabdominal aortic aneurysms treated with either CAAs or RSD between 2002 and 2022 at our institution. The diagnosis was confirmed by intraoperative, radiologic, or microbiological evidence of aortic infection. Perioperative events, 30-day and long-term mortality, reinfection, and reintervention were analyzed. RESULTS: Thirty patients (17 CAA, 13 RSD) with a mean age of 61 and 68 years, respectively, were identified. The infected aneurysm was most commonly suprarenal or infrarenal. Culture-negative infections were present in 47% of the CAA group and 54% in the RSD group. Early major morbidity was 57% and 54% for the CAA and RSD, respectively. Thirty-day mortality was similar between groups (18% vs. 23% CAA vs. RSD, P ≥ 0.99). Median follow-up was longer in the RSD group (14.5 months vs. 13 months). Overall survival at 1 and 5 years was 80.8% and 64.8% in the CAA group and 69.2% and 57.7% in the RSD group. Reinterventions only occurred with CAA repairs and indications included graft occlusion (2), multiple pseudoaneurysms and reinfection (1), and hemorrhagic shock caused by graft rupture (1). Freedom from reintervention at 1 and 3 years was 87.5% and 79.5% (CAA group) versus 100% and 100% (RSD, P = 0.06). Freedom from reinfection at 1 year was 100% in both groups, while at 3 years it was 90.9% for the CAA group and 100% for the RSD group (P = 0.39). CONCLUSIONS: Infected aortic and iliac aneurysms have high early morbidity and mortality. CAA and RSD had similar outcomes in our series; CAA trended toward higher reintervention rates. Both remain viable options for complex scenarios but require close surveillance.

Iliac Artery Tortuosity Index in Chinese Patients with or without Aortic Artery Aneurysms and Related Influencing Factors.

BACKGROUND: Iliac artery tortuosity is an important anatomical factor that influences the endovascular repair of aortic artery aneurysms. The influencing factors of the iliac artery tortuosity index (TI) have not been well studied. TI of iliac arteries and related factors in Chinese patients with and without abdominal aortic aneurysm (AAA) were studied in this study. METHODS: One hundred and ten consecutive patients with AAA and 59 patients without AAA were included. For patients with AAA, the diameter of the AAA was 51.9 ± 13.3 mm (24.7-92.9 mm). Those without AAA had no history of definite arterial diseases and came from a cohort of patients diagnosed with urinary calculi. The central lines of the common iliac artery (CIA) and external iliac artery were depicted. The actual length and the straight distance were measured and used to calculate the TI (actual length/straight distance). Common demographic factors and anatomical parameters were analyzed to identify any related influencing factors. RESULTS: For patients without AAA, the total TI of the left and right side was 1.16 ± 0.14 and 1.16 ± 0.13, respectively (P = 0.48). For patients with AAAs, the total TI in the left and right side was 1.36 ± 0.21 and 1.36 ± 0.19, respectively (P = 0.87). The TI in external iliac artery was more severe than that in CIA both in patients with and without AAAs (P < 0.01). Age was the only demographic factor found to be associated with TI in patients with AAA (Pearson's correlation coefficient r ≈ 0.3, P < 0.01) and without AAA (r ≈ 0.6, P < 0.01). For anatomical parameters, the diameter was positively associated with the total TI (left side: r = 0.41, P < 0.01; right side: r = 0.34, P < 0.01). The ipsilateral CIA diameter was also associated with the TI (left side: r = 0.37, P < 0.01; right side: r = 0.31, P < 0.01). The length of the iliac arteries was not associated with age or AAA diameter. Reduction of the vertical distance of the iliac arteries may be a common underlying reason for age and AAA. CONCLUSIONS: Tortuosity of the iliac arteries was probably an age-related problem in normal individuals. It was also positively correlated with the diameter of the AAA and the ipsilateral CIA in patients with AAA. Attention should be paid to the evolution of iliac artery tortuosity and its influence when treating AAAs.

A Multicenter Experience of Three Different "Iliac Branched" Stent Grafts for the Treatment of Aorto-Iliac And/Or Iliac Aneurysms.

BACKGROUND: The aim of study was to assess the safety and effectiveness of 3 different commercial iliac branch devices (IBDs): the Zenith Branch Iliac Endovascular Graft; the Gore Excluder Iliac Branch System and the E-liac Stent Graft System for the treatment of aorto-iliac or iliac aneurysms. METHODS: From January 2017 to February 2020, a retrospective reviewed was conducted on a total of 96 patients. Primary endpoint was IBD instability rate at 24 months. Secondary endpoints included onset of any endoleaks, buttock claudication, IBD-related reintervention and all-death rates, postoperative acute kidney, and changes in maximum diameter from baseline of the aortic aneurysmal sac. RESULTS: At 24 months, the branch instability rate was similar among the 3 IBDs employed [Jotec 1/24 (4.1%), Gore 1/12 (8.3%), Cook 6/47 (12.7%), P-value = 0.502]. As well, no statistical difference in terms of branch occlusion and branch-related endoleaks was observed. The Jotec group showed a significant decrease in maximum diameter from the baseline of the aortic aneurysmal sac when compared to the Gore group alone. No other differences were found relevant to the onset of any endoleaks, reinterventions, and all-death rates. At 24 months, the Kaplan-Meier estimate of survival freedom from any branch instability was 95.8%, 91.6%, and 86.8% for Jotec, Gore and Cook groups, respectively. CONCLUSIONS: The use of IBDs represents a safe method for preserving patency of the IIA during treatment of aorto-iliac or iliac aneurysms providing a low rate of IBD instability.

The Importance of the Hypogastric Artery Preservation during Treatment for Aortoiliac Aneurysms: A Prospective Single-Center Study.

BACKGROUND: To determine the importance of the hypogastric artery for the outcomes of survival, endoleaks, reinterventions, buttock claudication (BC), and perioperative mortality rate (PMR) in patients with aortoiliac aneurysms (AIA) receiving endovascular or open surgical (OS) repair. METHODS: This was a prospective consecutive cohort study of patients with AIA who underwent endovascular treatment or OS repair during the period of 2010-2021. Endovascular repair was performed with use of aortoiliac endoprosthesis associated with internal iliac artery (IIA) coil embolization and/or with iliac branch endoprosthesis (IBE) in order to preserve the IIA. The AIA OS repairs were performed with the artery ligation in order to exclude the IIA, or in some cases, the exclusion of the IIA was performed with an endosuture in the proximal stump of the artery. Three groups were identified in the postprocedural period: group 0 (no hypogastric arteries (HAs) preserved), group 1 (1 hypogastric artery preserved), and group 2 (2 hypogastric arteries preserved). RESULTS: A total of 91 patients were submitted to OS or endovascular surgery. Regarding the HA patency, there were 17 patients in group 0, 45 patients in group 1, and 29 patients in group 2. There were 17 cases of bowel ischemia (BI) (94.1% in group 0, 5.9% in group 1, and no cases in group 2, P < 0.001) most of them in group 0, with statistical significance, 12 cases of BC (91.7% in group 0, 8.3% in group 1, and no cases in group 2, P < 0.001), most of them in group 0, with statistical significance. The perioperative mortality was 14.3%, 13 patients (9 patients - 52.9% group 0, 3 patients - 6.7% group 1, and 1 patient - 3.4% group 2, P < 0.001). The linear regression analysis for survival rates showed that BI [P = 0.026 to hazard ratio (HR) = 1.69], emergency aortoiliac repair (P < 0.001, HR = 8.86), and number of HAs (P < 0.001, HR = 5.46) in postoperative were related to poorer survival rates in both univariate and multivariate analysis. The linear regression analysis showed that the number of HAs (P < 0.001, HR = 3.61) in postoperative, emergency aortoiliac repair (P = 0.002, HR 3.233), and cardiac disease (P = 0.048, HR = 3.84) were related to BI. CONCLUSIONS: In conclusion, the number of HA is crucial for adequate and safe outcomes after abdominal aortic aneurysm (AAA) repair. The main factors related to death were BI, emergency aortoiliac repair, and the number of HAs preserved. Moreover, the main factors related to BI were the number of HAs in postoperative, emergency aortoiliac repair, and cardiac disease.

Treatment of Aortoiliac Aneurysms: Compatibility of the E-liac Stent Graft (Artivion®, Iliac Branch Device) with Endurant II or IIs (Medtronic®, EVAR).

PURPOSE: Iliac branch devices (IBD) are widely used to treat aortoiliac aneurysms with an unfit distal landing zone for standard endovascular aneurysm repair (EVAR). The aim of this retrospective study was to examine the treatment of aortoiliac aneurysms with the combination of the Endurant II(s) stent graft system (Medtronic®) and the E-liac stent graft (Artivion®). MATERIALS AND METHODS: Data of all patients who underwent an EVAR combined with unilateral or bilateral IBD between January 2015 and January 2020 were analyzed. Primary outcomes were technical success at implantation (successful EVAR with IBD extension placement and patency of the grafts without type 1 or type 3 endoleak), and type 1b/3 endoleak, hypogastric artery patency and IBD-related reinterventions during follow-up. Secondary outcomes were all type 1 endoleak, all reinterventions, rupture, and mortality during follow-up. RESULTS: A total of 38 patients were treated with a combination of EVAR with IBD. Technical success was 94.7% (n = 36/38). The 30-day survival was 100%. Median follow-up time was 31 months (range 8-56). During follow-up, no patients developed type 1b or type 3 endoleak and all hypogastric arteries at the side of IBD remained patent. The overall reintervention rate at 12 months follow-up was 5.3% (n = 2/38) and the IBD-related reintervention rate was 2.6% (n = 1/38). CONCLUSION: The combination of the Endurant II(s) and the E-liac stent graft system is an effective and safe procedure for patients with an aortoiliac aneurysm. We confirm the high hypogastric artery patency rate using IBD. Furthermore, these devices have a high technical success rate even when it is combined with an Endurant II(s) EVAR main body.

Off-label use of an iliac branch device and a reversed iliac limb for a patient with a unilateral common iliac artery aneurysm and a narrow distal aorta: A case report.

INTRODUCTION: Current bifurcated aortic endografts are unsuitable for patients with a narrow distal aorta except AFX2, which is unavailable in South Korea. An iliac branch device (IBD) was introduced to exclude iliac aneurysms while preserving the pelvic circulation. With advancements in endovascular techniques, various attempts for outside instructions for use have been reported to be practicable in certain patients. PATIENT CONCERNS: A 58-year-old man was referred to our emergency room with an incidentally found left common iliac artery aneurysm (CIAA) in a general checkup. DIAGNOSES: Computed tomography angiogram showed a narrow distal aorta that tapered from 20 mm just below the renal artery to 13 mm at aortic bifurcation and a left isolated CIAA with a maximal diameter of 40 mm and 70 mm in length. INTERVENTIONS: After left hypogastric artery embolization, the Cook IBD was placed at the aortic bifurcation, and the Bard Covera Plus stent-graft was deployed from the IBD cuff to the left external iliac artery. Then, a reversed Medtronic Endurant iliac limb was implanted into the infrarenal aorta down to the proximal IBD. OUTCOMES: The stent grafts were patent without endoleak at the 6-month follow-up. LESSONS: In selected patients with an isolated CIAA with a narrow distal aorta, IBD can be used as a main body at the aortic bifurcation for successful aneurysm exclusion. However, considering the application of outside instructions for use, special attention and careful planning must be taken before the procedure.

Five-year outcomes from a prospective, multicenter study of endovascular repair of iliac artery aneurysms using an iliac branch device.

OBJECTIVE: We have reported the 5-year results of a pivotal prospective, multicenter study conducted in the United States of a specifically designed iliac branch endoprosthesis (IBE; W.L. Gore & Associates, Flagstaff, AZ) for endovascular repair of aortoiliac aneurysms and common iliac artery aneurysms. METHODS: A total of 63 patients (98.4% male; mean age, 70 years) with aortoiliac or common iliac artery aneurysms had undergone implantation of a single IBE device and a bifurcated aortoiliac stent graft. Patients with bilateral common iliac artery aneurysms (n = 22; 34.9%) had undergone either staged occlusion or surgical revascularization of the contralateral internal iliac artery before study enrollment. At 5 years, 36 of the 63 patients had completed the final study follow-up examinations, including clinical examinations (n = 35) and computed tomography (n = 32), with the results evaluated by an independent core laboratory and adverse events adjudicated by a clinical events committee. RESULTS: At 5 years, freedom from all-cause mortality was 85.7% and freedom from aneurysm-related mortality was 100%. The nine deaths that had occurred (range, 132-1898 days) were adjudicated as unrelated to the aneurysm or procedure. Primary patency of the internal and external iliac artery IBE limbs was 95.1% and 100%, respectively. No patients had experienced new-onset buttock claudication on the IBE side or self-reported new-onset erectile dysfunction. The common iliac artery diameter on the IBE side was either unchanged or had decreased by ≥5 mm in 30 of the 31 patients (96.8%) with a baseline (1 month) and 5-year (range, 1641-2006 days) computed tomography scan available. Of the 31 evaluable patients, 9 (29.0%) had had an increase of ≥5 mm in the aortic diameter, 5 of whom had had a concurrent type II endoleak. No type I or type III endoleaks or device migration were identified by the core laboratory. Six patients had undergone eight secondary interventions, including five interventions for a type II endoleak. The freedom from secondary intervention was 90.5%. CONCLUSIONS: The 5-year results of our prospective, multicenter study have confirmed the safety, efficacy, and durability of the IBE device for the treatment of aortoiliac and iliac artery aneurysms. The device effectively prevented common iliac artery aneurysm rupture, maintained the patency of the internal iliac artery, and avoided the complications associated with internal iliac artery sacrifice. Although common iliac artery aneurysm enlargement was rare, abdominal aortic enlargement was more common, suggesting that the outcomes of endovascular aneurysm repair might be different for patients with or without associated common iliac artery aneurysms.

Multiple concomitant arterial aneurysms in Behçet's disease.

BACKGROUND: Behçet's disease (BD) is a rare form of systemic vasculitis that affects small to large vessels. It is characterized by mucocutaneous, pulmonary, cardiovascular, gastrointestinal, and neurological manifestations. Large vessel involvement may occur in a third of cases. Veins are usually more affected than arteries. Furthermore aneurysms are the most frequent arterial complication. CASE PRESENTATION: A 41-year-old man presented with multiple arterial aneurysms. He had previous medical history of a right popliteal aneurysm treated with a reversed femoro-popliteal venous bypass, long-term steroids and immunosuppressive treatment. On admission, diagnostic computed tomography angiography revealed multiple aneurysms, including an 87 mm aneurysm of the femoro-popliteal bypass and an abdominal aortic and left common iliac artery aneurysm. He received an intensification of medical treatment with methylprednisolone and infliximab intravenous infusion. Aorto iliac artery aneurysms were treated by infrarenal bifurcated stent graft implantation. The aneurysm of the venous femoro-popliteal bypass was treated by explantation and prosthetic repair. One month later, he presented with acute right limb ischemia related to occlusion of the right limb of the stent graft despite anticoagulation which was treated by mechanical thrombectomy. CONCLUSIONS: Vascular BD can worsen the vascular outcome after surgery. Except in an urgent context, BD must be controlled before surgery. This case report illustrates the importance of combined medical and surgical management, with first BD activity control with corticosteroids and immunosuppressive treatment, then surgical or endovascular treatment.

Comparison Study of Iliac Branch Endoprosthesis when Used on and off Label.

BACKGROUND: The aim of this study is to compare how instructions for use (IFU) affected perioperative and intermediate term outcomes for common iliac artery aneurysms (CIAA) treated with the Gore Excluder iliac branch endoprosthesis (IBE). METHODS: A retrospective analysis was performed of all patients treated at two affiliated academic centers from September 2016 to May 2020. Outcomes were compared between IFU and nonIFU IBE cases. Criteria for nonIFU included: (1) use with a nonGore aortic endoprosthesis (n = 10), (2) isolated IBE (n = 3), and (3) requiring nondedicated covered stents for additional extension into a more suitable landing zone in the ipsilateral internal iliac artery or one of its branches (n = 11). Perioperative and intermediate term data were collected for both groups. The primary end points were free from the major adverse event (MAE) at 30 days and primary effectiveness at 1 year. RESULTS: A total of 51 CIAA (39 patients) were treated with an IBE. Overall, 15 patients were treated under IFU and 24 under nonIFU. The IFU group mean age was older (72 vs. 67 years, P = 0.03), and males (97%) were primarily treated. Comorbidities were similar except nonIFU had more patients with previous endovascular abdominal aortic aneurysm repair on presentation (0 vs. 4 cases, P = 0.04). Procedure (178 vs. 264 min, P = 0.02) and fluoroscopy (52 vs. 74 min, P = 0.04) times were longer in the nonIFU group. Technical success was 100% for both groups, and there was no difference in device related reintervention at 30 days (0 vs. 1, P = 0.44). There was no MAE in either group at 30 days. Intervention for any endoleak was similar between the groups (2 vs. 3, P = 0.94). Percent CIAA sac regression was similar between the groups (19% vs. 18%, P = 0.21). There was no difference for primary effectiveness at 1 year (93% vs. 92%, P = 0.85). There was one death per group at one year not related to an aortic or iliac cause. CONCLUSIONS: In properly selected patients with complex anatomy, IBE can be used with nondedicated aortic and internal iliac components with good early term outcomes.

Bilateral Implantation of Double-Branched Iliac Branch Devices for Endovascular Repair of Aorto-Bi-Iliac Aneurysm With Concomitant Hypogastric Aneurysms: The Quadruple Branch.

PURPOSE: The purpose of this report is to describe the use of a double-branched custom-made iliac branch device (IBD) for the endovascular repair of an aorto-bi-iliac aneurysm with concomitant bilateral hypogastric aneurysms. TECHNIQUE: A 61-year-old man on peritoneal dialysis underwent a computed tomography (CT) of the infrarenal aorta before planned kidney transplantation. The CT showed an asymptomatic aorto-bi-iliac aneurysm of 54 mm involving the hypogastric artery (HA) bilaterally (right HA 31 mm; left HA 40 mm). The treatment consisted of an endovascular aortic repair (EVAR) and the bilateral implantation of custom-manufactured IBDs with double inner branches to preserve both superior and inferior gluteal arteries. At 1 year follow-up, the patient remains free of symptoms and the postoperative CT showed a successfully excluded aneurysm with patent bridging stent grafts to all HA branches. CONCLUSION: The bilateral implantation of double-branched IBDs is a feasible technique. Preservation of both hypogastric arteries and its branches can be achieved with this technique and therefore decrease the risk of buttock claudication and other ischemic complications.

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.

Effect of preservation of antegrade hypogastric flow on development of claudication following aortoiliac aneurysm repair.

OBJECTIVE: The objective of this study was to compare the rate of development of buttock claudication in patients undergoing aortoiliac aneurysm repair with and without exclusion of antegrade hypogastric arterial flow. In the absence of convincing data, questions remain regarding the best management of hypogastric arterial flow to prevent the theoretical risk of buttock claudication. METHODS: The Veterans' Affairs Open Versus Endovascular Repair (OVER) Cooperative Study prospectively collected information on buttock claudication. Trial participants were specifically prompted both pre- and postoperatively to report the development of claudication symptoms at several anatomic levels. Of note, trial investigators were specifically trained to occlude the trunk hypogastric arterial, preserving the anterior and posterior divisions. Bayesian survival models were created to evaluate time to development of left, right, or bilateral buttock claudication according to the presence/absence of antegrade hypogastric perfusion. RESULTS: A total of 881 patients from the OVER trial with information regarding status of hypogastric flow were included in the analysis. Of these, 788 patients maintained bilateral antegrade hypogastric arterial perfusion, 63 had right hypogastric coverage/occlusion, and 27 had left hypogastric coverage/occlusion, whereas 3 patients had bilateral hypogastric coverage/occlusion. Just under 5% of all patients (n = 41) developed buttock claudication. After adjustment for smoking, chronic obstructive pulmonary disease, medications, study arm, preoperative activity level, body mass index, age, and diabetes, intervention-related changes to hypogastric perfusion had no effect on time to development of buttock claudication. A Maximum A Posteriori Kullback- Leibler misfit χ2 was 14.45 with 24 degrees of freedom, resulting in a goodness of fit P-value of P = .94, indicative of a good fit. CONCLUSIONS: OVER is the largest aneurysm treatment study to prospectively collect data related to the development of claudication as well as hypogastric preservation status. Despite this, we were unable to find evidence to support the assertion that preservation of antegrade hypogastric flow decreases the rate of development of buttock claudication symptoms. The low rate of development of buttock claudication overall and in the subgroups is striking.