Aneurysms - Presentation, Investigation & Therapy Flashcards
What is the definition of an aneurysm?
enlargement of an artery caused by weakness in the arterial wall
What is an abdominal aortic aneuruysm (AAA)?
localized enlargement of the abdominal aorta such that the diameter is greater than 3 cm or more than 50% larger than normal.
It involves rupture of all three layers of the artery.
What are presenting symptoms of a ruptured AAA?
5
- sudden, intense and persistent chest or back pain.
- painful pulsatile mass
- hypoperfusion (shock)
- hypotensive
- syncope
What is a false aneurysm?
A pseudoaneurysm, also known as a false aneurysm, is a collection of blood that forms between the two outer layers of an artery, the tunica media and the tunica adventitia.
A dissecting aneurysm forms between which layers in the arteries?
intima and tunica media
What is arteriomegaly and subaneurysmal dilatation?
dilatation of an artery less than the required size for aneurysm (i.e. <3cm in abdominal aorta).
Where do the majority of AAA’s occur?
between the renal arteries and the bifurcation of the abdominal aorta
What are some causes of AAA’s?
3
- degenerative (e.g. atheroma)
- connective tissue damage (e.g. Marfan’s)
- infection (e.g. mycotic aneurysm)
What are some risk factors associated with AAA’s?
5
male age smoking alcohol hypertension Fx
How do unruptured aneurysms often present?
asymptomatic
How are AAA’s often diagnosed?
3
- imaging (ultrasound, CTA)
- Hx/Fx
- clinical examination
Are AAAs screened for?
yes, men over 65 are screened
How is patient fitness for elective repair assessed?
6
- full Hx/examination
- exercise tolerance
- CPEX
- aortic morphology
- Bloods (U+E)
- ECHO
What is the outcome if screening for AAA shows aorta is 3 to 4.4 cm (small aneurysm)?
annual surveillance (e.g. US)
What is the outcome if screening for AAA shows aorta is 4.5-5.5 cm (medium aneurysm)?
3-monthly surveillance
What is the outcome if screening for AAA shows aorta is >5.5cm (large aneurysm)?
treatment offered
What is the first step in determining the best surgical intervention for AAA repair?
What information can we gather from this?
CT angiography
aortic morphology, is it good or bad
If the CTA reveals a patient has good anatomy/aortic morphology. what would be the best treatment option?
EVAR (endovascular aneurysm repair)
Outline what an EVAR is?
- endovascular procedure, accessed via femoral artery
- inputs stent into abdominal aorta to provide an alternative route for blood flow
What type of stent is usually used in EVAR?
- nitinol (nickel and titanium)
- with covering fabric
What are the contraindications to an EVAR?
- patient preference
- predictable lack of follow up
- other CIs
If a patient has unsuitable anatomy/aortic morphology, what would be their treatment path?
- laparotomy/open repair
- only if they are a fit candidate for surgery
If a patient was unfit for open repair surgery, what treatment options would be considered?
(3)
- EVAR
- snorkel
- balloon expandable stent
Why is an EVAR procedure preferred over open repair surgery?
4
- less invasive
- faster recovery
- lower risk of complications
- less risk of infection
