Editor's Choice - Sex Specific Differences in Abdominal Aortic Aneurysm Morphology Based on Fully Automated Volume Segmented Imaging: A Multicentre Cohort Study and Propensity Score Matched Analysis.

OBJECTIVE

Sex specific anatomical differences may contribute to observed disparities in outcomes and suitability for endovascular aneurysm repair (EVAR) between men and women with abdominal aortic aneurysms (AAAs). This study aimed to assess these differences using fully automated volume segmentation (FAVS) and explore implications for EVAR suitability.

METHODS

This was a retrospective, multicentre cohort study of patients undergoing elective AAA repair between 2013 and 2023 in three tertiary UK centres. Pre-operative computed tomography scans were analysed using FAVS software. Demographic and clinical outcome data were obtained from the National Vascular Registry. Propensity score matching (1:4 women:men) was performed, adjusting for age, cardiovascular risk, aortic size index (ASI), treatment modality, and centre. Morphological features and device specific likelihood to meet instructions for use (IFU) were compared by sex.

RESULTS

Of 1 455 eligible patients, 145 women were matched to 580 men. Despite similar ASI and cardiovascular risk profiles, women had statistically significantly narrower, shorter, and more angulated aneurysm necks (p < .001), smaller visceral and access vessel diameters, and greater thoracic aorta and thrombus index (p < .050). However, no statistically significant differences were found in calcification volume or vessel tortuosity. Women were statistically significantly less likely to meet IFU criteria across proximal, distal, and access vessel parameters (p < .001).

CONCLUSION

FAVS offers a scalable approach to pre-operative anatomical assessment and could guide future device design. Even after adjusting for body size and cardiovascular risk, women with AAA exhibit distinct vascular morphology that adversely impacts EVAR suitability. The development of low profile, durable stent grafts and strategies targeting hostile neck anatomy are critical to improving EVAR access and outcomes for women.