Abdominal Aortic Aneurysm Flashcards
What is an aneurysm?
An aneurysm is a permanent dilation of an artery to twice the normal diameter.
What gender is more susceptible to AAA?
Men
Higher risk if first-degree relative is affected.
What conditions may precipitate an AAA?
Atherosclerosis (most common)
Infection
Trauma
Genetic
What are infectious causes of an AAA?
Syphillis
E.Coli
Salmonella
What are genetic causes of AAA?
Marfan’s syndrome
Ehlers-Danlos syndrome
What is the pathology behind an AAA?
The result of tunica media degeneration within the arterial wall.
The result of macrophages recruited into the atheroma releasing enzymes that break down the collagen and elastin of the tunica media - leading to expansion.
Do most AAAs occur above or below the renal arteries?
Around 80% are infrarenal.
Most are retroperitoneal - if infraperitoneal, rapid death.
What happens in a ruptured AAA?
The wall of the aorta completely fails, with blood escaping into the abdominal cavity - around 75% die from this state.
How do most AAA present?
Asymptomatically - this is usually an incidental finding.
Some may have pain (this is a risk factor for rupture).
How does a ruptured AAA present?
A sudden onset abdominal pain which radiates to the back, alongside an expansible abdominal mass.
How is AAA diagnosed?
Abdominal USS.
Men over 65 are monitored for this.
What form of imaging is used to identify a ruptured AAA?
CT scan is only method which is effective.
How is a ruptured AAA usually diagnosed?
Clinically - needs urgent management.
At what dilation is an AAA managed electively?
Only surgically managed if >5.5cm.
