This MRCS Part B station is about vascular pathology.
Key Information
- An aneurysm is a focal dilatation in an artery to more than 50% its normal diameter.
- This equates to 3 cm or larger for the abdominal aorta.
- An abdominal aortic aneurysm normally results from degeneration of the media of the artery wall, normally secondary to atherosclerosis.
- The most common modifiable risk factor is smoking.
- Most AAAs are asymptomatic, and screening with ultrasound is being investigated for efficacy.
- They can also present as a result of pressure on surrounding structures, for instance causing a constant severe lower back pain.
- The main clinical presentation, however, is when AAAs rupture, leading to severe hypovolaemic shock and cardiovascular collapse.
- A classic clinical OSCE scenario is a patient with illiac fossa pain, who you discover is in shock - always consider a ruptured AAA in your differential and institute urgent investigation and resuscitation.
