Abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is usually asymptomatic and typically detected incidentally. In the minority of patients who experience symptoms, abdominal, back, and groin pain are typical.

Ultrasound remains the definitive test for initial diagnosis and screening. Imaging with computed tomography angiography or magnetic resonance angiography is used for anatomic mapping to assist with operative planning.

For small AAA detected as an incidental finding, surveillance is preferred to repair until the theoretical risk of rupture exceeds the estimated risk of operative mortality. Repair is indicated in patients with large asymptomatic AAA.

Repair options include open surgical repair and endovascular aneurysm repair (EVAR). Mortality during elective surgical repair is higher for women than for men for both open repair (7.0% vs. 5.2%) and EVAR (2.1% vs. 1.3%).

Complications of treatment include acute kidney injury, limb ischemia, spinal cord ischemia, anastomotic pseudoaneurysm, graft infection, graft limb occlusion, and distal embolization. Endoleak is a specific complication of EVAR.

AAA is a permanent pathologic dilation of the aorta with a diameter >1.5 times the expected anteroposterior (AP) diameter of that segment, given the patient's sex and body size.[1]Dehlin JM, Upchurch GR. Management of abdominal aortic aneurysms. Curr Treat Options Cardiovasc Med. 2005 Jun;7(2):119-30. http://www.ncbi.nlm.nih.gov/pubmed/15935120?tool=bestpractice.com [2]Chaikof EL, Blankensteijn JD, Harris PL, et al. Reporting standards for endovascular aortic aneurysm repair. J Vasc Surg. 2002 May;35(5):1048-60. https://www.doi.org/10.1067/mva.2002.123763 http://www.ncbi.nlm.nih.gov/pubmed/12021727?tool=bestpractice.com [3]Wanhainen A, Van Herzeele I, Bastos Goncalves F, et al. Editor's choice -- European Society for Vascular Surgery (ESVS) 2024 clinical practice guidelines on the management of abdominal aorto-iliac artery aneurysms. Eur J Vasc Endovasc Surg. 2024 Feb;67(2):192-331. https://www.ejves.com/article/S1078-5884(23)00889-4/fulltext http://www.ncbi.nlm.nih.gov/pubmed/38307694?tool=bestpractice.com The most commonly adopted threshold is a diameter of 3 cm or more.[4]Owens DK, Davidson KW, Krist AH, et al; US Preventive Services Task Force. Screening for abdominal aortic aneurysm: US Preventive Services Task Force recommendation statement. JAMA. 2019 Dec 10;322(22):2211-8. https://jamanetwork.com/journals/jama/fullarticle/2757234 http://www.ncbi.nlm.nih.gov/pubmed/31821437?tool=bestpractice.com [5]Isselbacher EM, Preventza O, Hamilton Black J 3rd, et al. 2022 ACC/AHA guideline for the diagnosis and management of aortic disease: a report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines. Circulation. 2022 Dec 13;146(24):e334-e482. https://www.doi.org/10.1161/CIR.0000000000001106 http://www.ncbi.nlm.nih.gov/pubmed/36322642?tool=bestpractice.com [6]American College of Radiology. ACR appropriateness criteria: screening for abdominal aortic aneurysm​. 2023 [internet publication]. https://acsearch.acr.org/docs/3194112/Narrative More than 90% of aneurysms originate below the renal arteries.[7]Kuivaniemi H, Elmore JR. Opportunities in abdominal aortic aneurysm research: epidemiology, genetics, and pathophysiology. Ann Vasc Surg. 2012 Aug;26(6):862-70. http://www.ncbi.nlm.nih.gov/pubmed/22794334?tool=bestpractice.com [Figure caption and citation for the preceding image starts]: Ultrasound of a 3.8 cm × 4.2 cm abdominal aortic aneurysmUniversity of Michigan/Dr G.R. Upchurch, Departments of Vascular Surgery and Radiology [Citation ends].