Sex-specific Differences in AAA Complexity

Study Overview
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Brief Summary
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A retrospective cohort study of computed tomography scans of AAA patients considered for repair, in order to identify sex specific differences in abdominal aortic aneurysm (AAA) metrics and the association between anatomical differences/features of complexity and adverse patient outcome.

Detailed Description
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A retrospective cohort study of computed tomography scans of AAA patients considered for repair. The study aims to, firstly, identify sex specific differences in abdominal aortic aneurysm (AAA) metrics utilising manual and automated image processing techniques; and secondly, if numbers are sufficient, explore the association between features of AAA complexity and adverse patient outcome.

Official Title
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Retrospective Cohort Analysis of Sex-specific Differences in Abdominal Aortic Aneurysm Complexity and Association With Adverse Outcomes

Conditions
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AAA - Abdominal Aortic Aneurysm

Intervention / Treatment
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* Diagnostic Test: CTA Aorta


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All adult patients with AAA receiving assessment +/- primary open or endovascular repair at participating centre from 1/1/2010 to 31/12/2020. Must have AAA >= 5cm. Must have CT imaging within 1 year of operation or definitive turn down for treatment. Exclusion Criteria: Insufficient CT imaging quality (>3mm slices) or lack of CT within 1 year of operation. Insufficient clinical data to establish risk factors or clinical outcomes. Ruptured aneurysm, aorto-iliac occlusive disease, isolated iliac aneurysm, penetrating aortic ulcer, dissection, juxta or supra-renal aneurysm. Secondary repair/not primary treatment decision for AAA repair.

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Men<br>Male participants | Diagnostic Test: CTA Aorta<br>* Computed Tomography Angiography - Aorta Whole<br>|
| Women<br>Female Participants | Diagnostic Test: CTA Aorta<br>* Computed Tomography Angiography - Aorta Whole<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sex-specific differences in thrombus burden | Volumetric assessment of aortic thrombus | Pre-operative CT | 
| Sex-specific differences in anatomical complexity | Anatomical as assessed by current IFU (instructions for use) criteria. (Anatomy within pre-specified vessel diameter, length, tortuosity and calcification criteria for insertion of endovascular stent graft for AAA repair.) | Pre-operative CT | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association between anatomical differences and adverse patient outcome for patients receiving operative repair - need for transfusion, risk of vessel injury, ischaemia (bowel or limb), renal injury and re-intervention/endoleak. | Post-operative outcomes | 30 days |