Abdominal Aoritc Aneurysm Flashcards
What is an aneurysm?
https://www.youtube.com/watch?v=FgcHtmry3iA
A localized, blood-filled balloon-like bulge in the wall of a blood vessel. The arteries most frequently involved are the abdominal aorta, iliac, popliteal, femoral artery and thoracic aorta (in decreasing frequency)
What are the different types of aneurysms?
- True aneurysm
- False aneurysm
What is a true aneurysm?
One that involves all three layers of the wall of an artery (intima, media and adventitia).
True aneurysms include atherosclerotic, syphilitic, and congenital aneurysms, as well as ventricular aneurysms that follow transmural myocardial infarctions (aneurysms that involve all layers of the attenuated wall of the heart are also considered true aneurysms).
What are the subtypes of true aneurysms?
- Fusiform
- Saccular
What is the difference between a fusiform and saccular true aneurysm?
The more common fusiform-shaped aneurysm bulges or balloons out on all sides of the blood vessel. A saccular-shaped aneurysm bulges or balloons out only on one side.
What disease processes are true aneurysms associated with?
- Hypertension
- Atherosclerosis
- Smoking
- Collagen abnormalities - e.g. Marfan’s, Ehler-Danlos
- Trauma
- Infection - syphilis, E. coli, Salmonella
What is a pseudo-aneurysm?
A collection of blood leaking completely out of an artery or vein, but confined next to the vessel by the surrounding tissue. Therefore, the surrounding tissues form the wall of the aneurysm, not the walls of the vessel. This blood-filled cavity will eventually either thrombose (clot) enough to seal the leak, or rupture out of the surrounding tissue.
What is the most common location for a AAA to occur?
Infrarenal - 95%
Which sex do AAA’s occur in more commonly?
Males
When does aortic dilation become classified as an aneurysm?
Exceeds 3.0 cm
or
Increases by 50% of normal circumference
What are the common sites for AAA’s to occur?
- Aorta
- Iliac artery
- Femoral Artery
- Popliteal artery
What are complications of AAA’s?
- Rupture
- Thrombosis/Embolism
- Fistulae
- Pressure on other structures
How would someone with an unruptured AAA present?
Asymptomatically - often discovered incidentally
If symptomatic:
- Central abdominal pain/back pain
- Distal embolic events - due to aneurysmal emboli formation
- Evidence of aortic occlusion - due to thrombus formation
How would someone with a ruptured AAA present?
- Intermittent/continuous abdominal pain - radiates to the back, iliac fossa or groins
- Collapse/Shock - hypovolaemic
- Expansile abdominal mass
What might you see on an abdominal examination in someone with an AAA?
Expansile abdominal mass