Abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) can present ruptured or unruptured.

Patients with a ruptured AAA may present with new abdominal and/or back pain, cardiovascular collapse, or loss of consciousness. Urgent imaging with bedside aortic ultrasound or computed tomography angiography (CTA) is required.

However, patients with an unruptured AAA are usually asymptomatic and their AAA is detected incidentally or through targeted screening. In the minority of patients who experience symptoms, abdominal, back, and groin pain are typical.

Ultrasound remains the first-line investigation for initial diagnosis and screening of an unruptured AAA. Imaging with CTA or magnetic resonance angiography is used for anatomical mapping to assist with operative planning.

Urgent surgical repair is indicated for patients with a ruptured or symptomatic AAA.

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

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

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

AAA is a permanent pathological 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]Johnston KW, Rutherford RB, Tilson MD, et al. Suggested standards for reporting on arterial aneurysms. J Vasc Surg. 1991 Mar;13(3):452-8. http://www.ncbi.nlm.nih.gov/pubmed/1999868?tool=bestpractice.com [2]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.[2]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 [3]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://www.doi.org/10.1001/jama.2019.18928 http://www.ncbi.nlm.nih.gov/pubmed/31821437?tool=bestpractice.com ​​​ More than 90% of aneurysms originate below the renal arteries.[4]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 x 4.2 cm AAAUniversity of Michigan, specifically the cases of Dr Upchurch reflecting the Departments of Vascular Surgery and Radiology [Citation ends].