Ballooning of a weakened section of vessel wall on the abdominal aorta, typically below the level of the lumbar vertebrae, potentially causing dissection and/ or

rupture of the aorta leading to profound shock and rapid mortality.

Abdominal Aortic Aneurysm (AAA)

Common risk factors: Cardiac (Family history, Male > 50yo, smoking, HT, diabetes, hyperlipidaemia, obesity, poor diet, sedentary lifestyle, IHD) Other factors: trauma, infection

Weakening/ damage to endothelium of abdominal aorta. Nb. Possibly more susceptible to vessel wall damage than other areas of the descending aorta

Bulging in section of aorta wall (>3cm in diameter)

= ANEURYSM

Vague abdominal &/ or back pain

Pulsatile or palpable abdominal mass (usually >4cm in diameter)

Hypotension & associated tachycardia & syncope

Nausea & vomiting

Tear in aorta tunica intima

Blood enters between intima, media & adventitia layers

High pressure causes blood to track causing false lumen

between layers = DISSECTION

Turbulent & altered blood flow within artery

Thrombus formation

Altered distal blood supply

Absent or uneven distal pulses

Uneven distal skin colour & temperature

Distal tissue ischaemia

Sudden & severe back, abdominal, flank “tearing” pain

Nerve stimulation causes radiating groin or testicular pain

Pulsatile or palpable abdominal mass (usually >4cm in diameter)

Hypotension & associated tachycardia

Nausea & vomiting (possibly due to hypotension and/ or pain

stimulus)

Clot formation/ hardening of false lumenComplete rupture of artery wall

Rapid & continuous haemorrhage into retroperitoneum

Syncope (decrease cerebral perfusion)

Profound shock & DEATH