Skip to Main Content

We have a new app!

Take the Access library with you wherever you go—easy access to books, videos, images, podcasts, personalized features, and more.

Download the Access App here: iOS and Android. Learn more here!

  • • Permanent aortic dilation (at least 50%)

    • Classified by etiology (degenerative, inflammatory, mechanical, congenital, dissecting) and by shape (saccular, fusiform)

    • Up to 25% of patients have symptoms of aortoiliac occlusive disease as well

    • Most are infrarenal; decreased vasa vasorum and elastic lamellae may predispose to aneurysm formation

    • Rupture risk correlates with size, following law of LaPlace

    • Average expansion rate of 0.4 cm/y depends on aneurysm size, diastolic blood pressure, and chronic obstructive pulmonary disease (COPD)

    • For AAA measuring 5.0-5.5 cm, rupture risk is 40% at 5 years

    Suprarenal: Uncommon; extends proximal to renal arteries; low risk for rupture until exceeds 6-7 cm

    Ruptured: Most often ruptures posterolaterally to left; if exsanguination delayed, likely contained rupture that eventually becomes free rupture

    Inflammatory: Characterized by inflammatory response external to aneurysmal wall, with inflammation usually confined to anterior aorta; 25% have ureteral obstruction, which results in dense, shiny fibrotic reaction enveloping adjacent viscera

    Infected (mycotic): Bacterial contamination of preexisting aneurysm (different from Salmonella causing false aneurysm); gram-negative infections result in higher rupture rates


  • • Ruptured AAA is the 13th leading cause of death in the United States (15,000 deaths yearly)

    • Present in 2% of population and incidence is increasing

    • More men affected than women (4:1)

    • 5% of patients with coronary artery disease have AAA

    • 50% of patients with femoral or popliteal aneurysms have AAA

    • 19% incidence among first-degree relatives

    Rare causes:

    • -Marfan syndrome

      -Ehlers-Danlos syndrome

      -Behçet disease


      -Long-term sequelae of aortic dissection


    • -Smoking

      -Hypertension (HTN)


    • Diabetes appears to exert protective effect

    • Increased incidence of rupture during fall and winter months

    Strep, Haemophilus, Staph, E coli, other gram-negative pathogens, and fungi identified in infected AAA

Symptoms and Signs

  • • Rarely produces symptoms if intact

    • Painless, pulsatile abdominal mass above umbilicus; may be uncomfortable on palpation

    • Palpation may be difficult in obese patients

    • Rarely produces back pain from pressure on nerves

    • Severe paincaused by inflammatory or ruptured AAA or acute expansion

    • Congestive heart failure from aortocaval fistula, GI bleed from duodenal erosion, and pyelonephritis from ureteral obstruction are rare

    • Rupture causes sudden, severe abdominal/back pain radiating to back or inguinal area, faintness or syncope, shock; often tender pulsatile mass present

    Triad for rupture: Pain, pulsatile abdominal mass, hypotension found in < 67% of patients

    Inflammatory: Abdominal pain, tender AAA

    Infected: Rapidly enlarging tender pulsatile mass, fever

Laboratory Findings

  • • CBC abnormal

Imaging Findings

  • Abdominal x-ray: 20% calcifications in outer aortic wall on lateral view


    • -Inexpensive screening test, measures size and position

      -Used in cases of groin pseudoaneurysm to evaluate proximal anastomosis in abdomen

    CT scan

    • -Diagnostic, accurate sizing, and provides information about anatomy: renal anomalies, retroaortic renal veins, ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.