Image-based assessment of aortoiliac aneurysm anatomical characteristics in patients from the global iliac branch study.

OBJECTIVE: Endovascular repair is the preferred treatment for aortoiliac aneurysm, with preservation of at least one internal iliac artery recommended. This study aimed to assess pre-endovascular repair anatomical characteristics of aortoiliac aneurysm in patients from the Global Iliac Branch Study (GIBS, NCT05607277) to enhance selection criteria for iliac branch devices (IBD) and improve long-term outcomes. METHODS: Pre-treatment CT scans of 297 GIBS patients undergoing endovascular aneurysm repair were analyzed. Measurements included total iliac artery length, common iliac artery length, tortuosity index, common iliac artery splay angle, internal iliac artery stenosis, calcification score, and diameters in the device's landing zone. Statistical tests assessed differences in anatomical measurements and IBD-mediated internal iliac artery preservation. RESULTS: Left total iliac artery length was shorter than right (6.7 mm, P = .0019); right common iliac artery less tortuous (P = .0145). Males exhibited greater tortuosity in the left total iliac artery (P = .0475) and larger diameter in left internal iliac artery's landing zone (P = .0453). Preservation was more common on right (158 unilateral, 34 bilateral) than left (105 unilateral, 34 bilateral). There were 192 right-sided and 139 left-sided IBDs, with 318 IBDs in males and 13 in females. CONCLUSION: This study provides comprehensive pre-treatment iliac anatomy analysis in patients undergoing endovascular repair with IBDs, highlighting differences between sides and sexes. These findings could refine patient selection for IBD placement, potentially enhancing outcomes in aortoiliac aneurysm treatment. However, the limited number of females in the study underscores the need for further research to generalize findings across genders.

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.

Endovascular repair of an abdominal aortic aneurysm with external iliac artery occlusion using VBX as the contralateral leg via axillary delivery: A case report.

RATIONALE: A hostile iliac access route is an important consideration when enforcing endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAA). Herein, we report a case of AAA with unilateral external iliac artery occlusion, for which bifurcated EVAR was successfully performed using a single femoral and brachial artery access. PATIENT CONCERNS: A 76-year-old man who had undergone surgery for lung cancer 4.5 years prior was diagnosed AAA by computed tomography (CT). DIAGNOSIS: Two and a half years before presentation, CT revealed an infrarenal 48 mm AAA, which had enlarged to 57 mm by 2 months preoperatively. CT identified occlusion from the right external iliac artery to the right common femoral artery, with no observed ischemic symptoms in his right leg. The right external iliac artery, occluded and atrophied, had a 1 to 2 mm diameter. INTERVENTION: Surgery was commenced with the selection of a Zenith endovascular graft (Cook Medical) with an extended body length. Two Gore Viabahn VBX balloon expandable endoprosthesis (VBX; W.L. Gore & Associate) were delivered from the right axilla as the contralateral leg. OUTCOMES: CT scan on the 2nd day after surgery revealed no endoleaks. LESSONS: While the long-term results remain uncertain, this method may serve as an option for EVAR in patients with unilateral external iliac artery occlusion.

Immunoglobulin G4-Related Disease Complicating Ruptured Isolated Iliac Artery Aneurysm: A Complex Management Dilemma.

BACKGROUND Managing IgG4-related disease (IgG4-RD) in the context of vascular complications, such as aneurysms, poses significant challenges, particularly when considering surgical intervention options. The risk of rupture and infection in patients on long-term glucocorticoid therapy complicates treatment decisions. CASE REPORT A 63-year-old woman with a history of IgG4-RD presented with a ruptured right iliac artery aneurysm. She was on long-term oral glucocorticoid therapy. Initial emergency endovascular stent graft implantation was followed by embolization for suspected arterial bleeding and subsequent Salmonella bacteremia. Repeated hospitalizations involved stent graft removal and surgical repair due to persistent infection. Over 2 years, the patient required multiple pelvic drainages and long-term antibiotic and prednisolone therapy, yet her quality of life remained compromised. CONCLUSIONS Our case highlights the unique challenges and considerations in the treatment of IgG4-related aneurysms. Patients with IgG4-RD who are on long-term oral glucocorticoids have an inherent risk of aneurysm rupture. We believe regular follow-ups to monitor the progression of the aorta and iliac arteries into aneurysms are essential. For patients who have developed aneurysms, it is advisable to reduce the dosage of glucocorticoids or even consider surgical treatment as soon as possible. As for the choice of surgical method, there is no consensus yet. While endovascular treatment is less invasive and quicker, it can increase the risk of rupture and bleeding. Open surgery might be a better option. More data are needed to make a definitive judgment.

Five-year outcomes for bell bottom, iliac branch endoprosthesis, and coil and cover approaches from the GREAT registry.

OBJECTIVE: There are a variety of methods used today to treat common iliac aneurysms with endovascular techniques. Of these approaches, little is known about whether a particular limb strategy influences endoleak, reintervention, or aneurysm regression rates. We present 5-year data comparing endoleak, stent graft migration, fracture, aneurysm sac dynamics, and aortic rupture rates among patients treated with bell bottom limbs (BB), iliac branch endoprosthesis (IBE), and coil and cover (CC) approaches from the Global Registry for Endovascular Aortic Treatment registry. Secondary end points were all-cause mortality, stroke, reintervention, and paraplegia. METHODS: Subjects from the GORE Global Registry for Endovascular Aortic Treatment were enrolled over a 5-year period from October 2017 to August 2022. We included 924 subjects in this study. Statistical data was generated on R software and limb groups were compared using the Pearson's χ2 test and the Kruskal-Wallis rank-sum test. RESULTS: We found no statistical difference in endoleak rates, stent graft migration, fracture, or aortic rupture when stratified by limb strategy. There was no difference between limb approaches with regard to aneurysm sac dynamics among those with abdominal aortic aneurysms and common iliac aneurysms. Similarly, no statistical difference between limb strategies was found in all-cause mortality, stroke, paraplegia, or reintervention rates. Among patients that required an additional graft during reintervention, the highest rates were found within the IBE group 8.6%, compared with BB group 2.2% and CC group 1.3% (P = .006). CONCLUSIONS: Overall, there was no difference among limb strategies in endoleak rates, stent graft migration, aneurysm sac dynamics, aortic rupture rates, or our secondary end points. Increased rates of reintervention requiring an additional graft within the IBE group is noteworthy and must be weighed against the adverse effects of hypogastric sacrifice with the CC approach or potentially less advantageous seal zones in the BB approach. This finding suggests that all limb approaches have equivalent effectiveness in managing the aneurysmal common iliac artery; thus, the choice of limb strategy should be individualized and remain at physician discretion. Future research should include a more robust sample size to reproduce these findings.

Prognostic factors after open and endovascular repair for infected native aneurysms of the abdominal aorta and common iliac artery.

OBJECTIVE: Infected native aneurysms (INAs) of the abdominal aorta and iliac arteries are uncommon, but potentially fatal. Endovascular aneurysm repair (EVAR) has recently been introduced as a durable treatment option, with outcomes comparable to those yielded by conventional open repair. However, owing to the rarity of the disease, the strengths and limitations of each treatment remain uncertain. The present study aimed to separately assess post-open repair and post-EVAR outcomes and to clarify factors affecting the short-term and late prognosis after each treatment. METHODS: Using a nationwide clinical registry, we investigated 600 patients treated with open repair and 226 patients treated with EVAR for INAs of the abdominal aorta and/or common iliac artery. The relationships between preoperative or operative factors and postoperative outcomes, including 90-day and 3-year mortality and persistent or recurrent aneurysm-related infection, were examined. RESULTS: Prosthetic grafts were used in >90% of patients treated with open repair, and in situ and extra-anatomic arterial reconstruction was performed in 539 and 57 patients, respectively. Preoperative anemia and imaging findings suggestive of aneurysm-enteric fistula were independently associated with poor outcomes in terms of both 3-year mortality (hazard ratio [HR], 1.62; 95% confidence interval [CI], 1.01-2.62; P = .046, and HR, 2.24; 95% CI, 1.12-4.46; P = .022, respectively) and persistent or recurrent infection (odds ratio [OR], 2.16; 95% CI, 1.04-4.49; P = .039, and OR, 4.96; 95% CI, 1.81-13.55; P = .002, respectively) after open repair, whereas omental wrapping or packing and antibiotic impregnation of the prosthetic graft for in situ reconstruction contributed to improved 3-year survival (HR, 0.60; 95% CI, 0.39-0.92; P = .019, and HR, 0.53; 95% CI, 0.32-0.88; P = .014, respectively). Among patients treated with EVAR, abscess formation adjacent to the aneurysm was significantly associated with the occurrence of persistent or recurrent infection (OR, 2.24; 95% CI, 1.06-4.72; P = .034), whereas an elevated preoperative white blood cell count was predictive of 3-year mortality (HR, 1.77; 95% CI, 1.00-3.13; P = .048). CONCLUSIONS: Profiles of prognostic factors differed between open repair and EVAR in the treatment of INAs of the abdominal aorta and common iliac artery. Open repair may be more suitable than EVAR for patients with concurrent abscess formation.

Computational Comparison of the Mechanical Behavior of Aortic Stent-Grafts Derived from Auxetic Unit Cells.

PURPOSE: Inappropriate stent-graft (SG) flexibility has been frequently associated with endovascular aortic repair (EVAR) complications such as endoleaks, kinks, and SG migration, especially in tortuous arteries. Stents derived from auxetic unit cells have shown some potential to address these issues as they offer an optimum trade-off between radial stiffness and bending flexibility. METHODS: In this study, we utilized an established finite element (FE)-based approach to replicate the mechanical response of a SG iliac limb derived from auxetic unit cells in a virtual tortuous iliac aneurysm using a combination of a 180° U-bend and intraluminal pressurization. This study aimed to compare the mechanical performance (flexibility and durability) of SG limbs derived from auxetic unit cells and two commercial SG limbs (Z-stented SG and circular-stented SG models) in a virtual tortuous iliac aneurysm. Maximal graft strain and maximum stress in stents were employed as criteria to estimate the durability of SGs, whereas the maximal luminal reduction rate and the bending stiffness were used to assess the flexibility of the SGs. RESULTS: SG limbs derived from auxetic unit cells demonstrated low luminal reduction (range 4-12%) with no kink, in contrast to Z-stented SG, which had a kink in its central area alongside a high luminal reduction (44%). CONCLUSIONS: SG limbs derived from auxetic unit cells show great promise for EVAR applications even at high angulations such as 180°, with acceptable levels of durability and flexibility.

Results Following Stent-Graft Coverage of the Hypogastric Artery in the Management of Aortoiliac Aneurysms in Endovascular Aneurysm Repair.

<b><br>Aim:</b> The aim of our study was to assess the outcomes of stent-graft coverage of the hypogastric artery in the management of aortoiliac aneurysms with endovascular aneurysm repair (EVAR).</br> <b><br>Material and methods:</b> From January 2013 to March 2017, a total of 93 patients with aortoiliac aneurysms were treated with EVAR, which required occlusion of one or both of the hypogastric arteries. The patients of the Department of General, Vascular, Endocrine and Transplant Surgery were included in the study continuously and all procedures were elective.</br> <b><br>Results:</b> A total of 93 patients with aortoiliac aneurysms required a unilateral or bilateral procedure. Six patients were excluded from our study because they did not appear at their follow-up appointments. The study included 87 patients (80 men; mean age 71.9 (7.9) years, range 54-88), of which 30 had a unilateral procedure and 57 had a bilateral procedure. In 8 procedures (5.55%, n = 7) there was a type II endoleak that resolved during follow-up and required no surgical intervention. In 10 procedures (6.94%, n = 10) there was a type IB endoleak, with 8 procedures requiring surgical re-intervention in the form of an extension. In 12 procedures (8.33%, n = 9), the hypogastric artery thrombosed.</br> <b><br>Conclusion:</b> Coverage of the hypogastric artery by stent-graft has been proven to be a safe procedure, but there is still a risk of type II endoleak. Although 5.55% (n = 7) of the procedures in our study had a type II endoleak, none required surgical intervention.</br>.

Results of iliac branch devices for hypogastric salvage after previous aortic repair.

OBJECTIVE: The aim of this multicentric study was to assess the "REsults of iliac branch deviceS for hypogastriC salvage after previoUs aortic rEpair (RESCUE)." METHODS: All consecutive patients who underwent implantation of iliac branch devices (IBDs) after previous open aortic repair (OAR) or endovascular aortic repair (EVAR) at seven centers were captured. The study cohort was divided into two groups according to the type of repair originally performed. Early outcomes included immediate technical success and perioperative adverse events. Late outcomes included survival, side branch (SB) primary patency, SB instability, and new onset buttock claudication. RESULTS: A total of 94 patients (82 male) were included in the study, 10 of them received bilateral implantation of IBDs. This resulted in a total of 104 devices included in the final analysis. Indication for treatment were endoleak 1b or progressive iliac aneurysmal degeneration or distal para-anastomotic aortic aneurysms; 73 were implanted after previous EVAR and 31 after previous OAR. Technical success was 100% in both groups. The 3-year rate of freedom from SB instability was 90.1% after previous EVAR and 85.4% after previous OAR, respectively (P = .05). The 3-year estimates of SB primary patency were significantly lower in patients who had received OAR as compared with those that had received EVAR (89.8% vs 94.9%; P = .05). CONCLUSIONS: Endovascular treatment with IBDs following previous OAR or EVAR is safe and effective up to 3 years. Freedom from SB instability during follow-up was lower in patients who had previously undergone OAR than EVAR.

Ruptured abdominal aorto-iliac aneurysms: Diagnosis, treatment, abdominal compartment syndrome, and role of simulation-based training.

Ruptured abdominal aortic aneurysms (rAAA), with or without iliac involvement, are a life-threatening scenario with high mortality even after surgical therapy. Several factors have contributed to improving perioperative outcomes in recent years, including the progressive use of endovascular aortic repair (EVAR) and intraoperative balloon occlusion of the aorta, a dedicated treatment algorithm with centralization of care to high-volume centres, and optimized perioperative management protocols. Nowadays, EVAR is applicable in the majority of scenarios even in the emergency setting. Among the factors that influence the postoperative course of rAAA patients, abdominal compartment syndrome (ACS) is a rare but life-threatening complication. As its early clinical diagnosis is often missed but crucial to initiate an emergent surgical decompression therapy, dedicated surveillance protocols and transvesical measurement of the intraabdominal pressure are key for prompt diagnosis and immediate treatment of ACS. Further improvement of rAAA patients' outcome may be achieved by the implementation of simulation-based training (of both technical and non-technical skills for surgeons as well as all involved healthcare personnel in multidisciplinary teams) and by transfer of all rAAA patients to specialized vascular centres with advanced experience and high caseload.

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.

Analysis of Repair Type and Hypogastric Artery Antegrade Perfusion and Erectile Function following Repair of Abdominal Aortic Aneurysms.

BACKGROUND: Published reports suggest that exclusion of antegrade hypogastric artery flow may have deleterious effects on erectile function after abdominal aortic aneurysm (AAA) repair. Off-label and open surgical hybrid procedures and, more recently, purpose-built branched devices have been developed to maintain antegrade pelvic perfusion in patients undergoing endovascular repair. Maintaining antegrade perfusion may reduce a spectrum of risks, including buttock claudication, colorectal ischemia, and spinal cord ischemia when patients undergo subsequent thoracic aortic procedures, as well as erectile dysfunction (ED). This project specifically focuses on erectile function, and analyzes baseline associations and relationships of hypogastric artery exclusion on changes in erectile function following aneurysm repair. METHODS: Male patients in the Veterans Affairs Open Versus Endovascular Repair (CSP#498; OVER) Trial had erectile function assessed preoperatively and postoperatively by administration of the International Index of Erectile Function-5 questionnaire. Bayesian mixed-effects regression models were created with the outcome variable (erectile function) treated as a latent variable. Primary effects of differences in erectile function between groups with and without preservation of bilateral antegrade hypogastric flow were compared. RESULTS: 876 men (442 randomized to endovascular repair) were enrolled in the trial and included in the analysis comparing treatment assignment. There is significant ED in elderly men with aortic aneurysm at baseline. Over 5 years of follow-up, there is modest decrease in erectile function and the endovascular group has improved function compared to open repair (0.082; 95% credible interval (CI) 0.008 and 0.155). A fifth of patients did not have bilateral preservation of antegrade hypogastric artery perfusion, with no difference in erectile function by univariate analysis. A more detailed regression analysis was applied--and after adjustment for baseline score, age, beta blocker use, diabetes, activity level, ejection fraction, preoperative ankle-brachial indices and time--preservation of both antegrade hypogastric arteries' perfusion showed transient improvement in survey scores compared to occlusion of at least 1 hypogastric artery at 6 months and 12 months after treatment, although this was not sustained at 60 months (score change: 0.046; 95% CI: -0.123, 0.215). Retesting this model in the cohort with complete data as a sensitivity analysis did not meaningfully change the conclusions. CONCLUSIONS: In this large prospective aneurysm treatment trial with systematic measurement of erectile function with a validated instrument, endovascular repair is associated with improved erectile function. Preservation of antegrade hypogastric flow with any repair is associated with early improved erectile function; however, it is not a sustained benefit. There is limited benefit of maintaining bilateral hypogastric artery perfusion for this specific indication in unselected men undergoing AAA repair.

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.