natural history of abdominal aortic aneurysm (AAA)

Last reviewed 01/2018

Natural history of the condition is characterised by progressive expansion. The risk of rupture increases with the increase in size of the aneurysm (1).

Risk factors associated with expansion and rupture of AAA includes (2):

  • expansion
    • advanced age
    • severe cardiac disease
    • previous stroke
    • tobacco use
    • cardiac or renal transplant
  • rupture
    • female gender
    • large initial aneurysm diameter
    • low forced expiratory volume in one second (FEV1)
    • higher mean blood pressure
    • current tobacco use (length of time smoking>>amount)
    • cardiac and renal transplant

Growth rates for AAA (3):

aneurysm diameter

average annual expansion rate

3.0 to 3.9 cm

1 to 4 mm

4.0 to 6.0 cm

3 to 5 mm

> 6.0 cm

7 to 8 mm

Absolute risk of rupture for AAA (3):


aneurysm diameter

absolute lifetime risk of rupture

5 cm

20%

6 cm

40%

7 cm

50%

Reference: