The anatomical distribution of iliac aneurysms: is there an embryological basis?

Prevalence of aortic aneurysms and dissections in patients with systemic vessel aneurysms and dissections; matched case-control study using a national sample cohort

Objective

Aneurysms in systemic arteries are rare, and little is known about their relationship with aortic aneurysms. In this study, we aimed to evaluate the prevalence of aortic aneurysms and dissections (AAD) in patients with other systemic vessel aneurysms and dissections (OVAD) and identify their potential risk factors.

Methods

This cross-sectional study used a nationwide representative cohort sample from the Korea National Health Insurance Service-National Sample Cohort database. We defined OVAD as systemic vessel aneurysms and dissections excluding intracranial and aortic dissections and aneurysms. With a total of 690 OVAD patients and 2,760 non-OVAD matched controls, we investigated the prevalence of AAD in patients with OVAD and potential risk factors for their concurrence using the χ2 test and logistic regression.

Results

The prevalence of AAD in patients with OVAD was 10.6% (73/690) and 0.3% (9/2,760) in patients with non-OVAD. The adjusted odds ratio (OR) for having concurrent AAD with OVAD was 37.56 (95% CI: 18.29-77.12, p < 0.001) after stratification by sex, age, income, region of residence and after adjustment for hypertension, diabetes mellitus, dyslipidemia, and extent of disability. The adjusted ORs of AAD were significantly higher in females [adjusted OR = 47.63 (95% CI: 10.72-211.55)], and individuals aged ≥60 years [adjusted OR = 28.18 (95% CI: 13.42-59.17)], as well as those without hypertension [adjusted OR = 95.44 (95% CI: 18.21-500.23)], diabetes mellitus [adjusted OR = 46.39 (95% CI: 18.85-114.17)], without dyslipidemia [adjusted OR = 60.99 (95% CI: 20.83-178.56), p < 0.001 for all]. The prevalence of AAD significantly differed by according to specific sites of OVAD in carotid artery, upper extremity artery, iliac artery, lower extremity artery, and splanchnic artery (p < 0.001 for all).

Conclusions

The prevalence of AAD in patients with OVAD was 37.56 times higher than that in the matched population. We may approach aneurysms as systemic diseases and further investigations of pathophysiology would help to clarify the relationships between AAD and OVAD.

Ultrasound Assisted On-Table Management of Type III Endoleak at Endovascular Repair of Isolated Giant Common Iliac Aneurysm

Objectives

This report presents the endovascular treatment of a large isolated common iliac artery aneurysm, focusing on the use of on table ultrasonography to characterise and treat an early endoleak that could not be defined by angiography alone.

Report

A 58 year old man presented with an asymptomatic, large (13cm) left common iliac artery aneurysm (LCIAA) whilst being investigated for change in bowel habit. This was treated successfully via a percutaneous approach using left internal iliac embolisation followed by endovascular aneurysm repair (EVAR) with deployment of an aorto-uni-iliac converter system from the LCIA origin to the external iliac artery. A non-characterised endoleak at the end of the procedure was shown to be a type IIIb endoleak by application of immediate on table ultrasonography, allowing immediate supplementary targeted stent graft deployment to cover the leaking segment.

Discussion

The patient was discharged uneventfully and will remain on follow up. On table ultrasonography allowed both localisation and characterisation of an immediate intra-procedural endoleak and confirmed cessation of the endoleak with supplementary stent grafting and thrombosis within the sac.

Conclusions

Isolated CIAA is rare, and endovascular therapy is appropriate for them, given that open surgery, whilst feasible, carries a high morbidity and mortality risk. Application of on-table ultrasound allows definition and targeted treatment of endoleaks, reducing the need for further intervention at a later stage, and thus also reducing the risk of continued pressurisation of the large sac post-EVAR till the next surveillance episode.

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Isolated common iliac artery aneurysms (CIAAs) are very rare.

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They can be asymptomatic but have a high risk of rupture.

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Open repair is high risk and associated with high morbidity/mortality.

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This paper highlights successful endovascular repair of a giant isolated CIAA.

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On table ultrasound helps immediately to characterise and treat endoleaks at EVAR.

A comparison of hemodynamic metrics and intraluminal thrombus burden in a common iliac artery aneurysm

Aneurysms of the common iliac artery (CIAA) are typically found in association with an abdominal aortic aneurysm (AAA). Isolated CIAAs, in the absence of an AAA, are uncommon. Similar to AAAs, CIAA may develop intraluminal thrombus (ILT). As isolated CIAAs have a contralateral common iliac artery for comparison, they provide an opportunity to study the hemodynamic mechanisms behind ILT formation. In this study, we compared a large isolated CIAA and the contralateral iliac artery using computational fluid dynamics to determine if hemodynamic metrics correlate with the location of ILT. We performed a comprehensive computational fluid dynamics study and investigated the residence time of platelets and monocytes, velocity fields, time-averaged wall shear stress, oscillatory shear index, and endothelial cell activation potential. We then correlated these data to ILT burden determined with computed tomography. We found that high cell residence times, low time-averaged wall shear stress, high oscillatory shear index, and high endothelial cell activation potential all correlate with regions of ILT development. Our results show agreement with previous hypotheses of thrombus formation in AAA and provide insights into the computational hemodynamics of iliac artery aneurysms.

Inhibition of development of abdominal aortic aneurysm by glycolysis restriction

OBJECTIVE

The mechanisms underlying abdominal aortic aneurysm development remain unknown. We hypothesized that acceleration of glucose metabolism with the upregulation of glucose transporters is associated with abdominal aortic aneurysm development.

METHODS AND RESULTS

Enhanced accumulation of the modified glucose analogue 18 fluoro-deoxyglucose by positron emission tomography imaging in the human abdominal aortic aneurysm was associated with protein expressions of glucose transporters-1 and -3, assessed by Western blot. The magnitude of glucose transporter-3 expression was correlated with zymographic matrix metalloproteinase-9 activity. Intraperitoneal administration of glycolysis inhibitor with 2-deoxyglucose significantly attenuated the dilatation of abdominal aorta induced by periaortic application of CaCl(2) in C57BL/6J male mice or reduced the aneurysmal formation in angiotensin II-infused apolipoprotein E knockout male mice. In monocytic cell line induced by phorbol 12-myristate 13-acetate or ex vivo culture obtained from human aneurysmal tissues, 2-deoxyglucose abrogated the matrix metalloproteinase-9 activity and interleukin-6 expression in these cells/tissues. Moreover, 2-deoxyglucose attenuated the survival/proliferation of monocytes and the adherence of them to vascular endothelial cells.

CONCLUSIONS

This study suggests that the enhanced glycolytic activity in aortic wall contributes to the pathogenesis of aneurysm development. In addition, pharmacological intervention in glycolytic activity might be a potential therapeutic target for the disorder.