Abdominal Aortic Aneurysm (AAA) Flashcards
Are abdominal aortic aneurysms typically suprarenal or infrarenal?
Infrarenal (below renal arteries)
What is an abdominal aortic aneurysm?
A permanent aortic dilation exceeding 50% where the diameter is greater than 3cm
What are risk factors of an AAA?
(Many are idiopathic)
Connective tissue disorders
Smoking
Obesity
Hypertension
Trauma
Family history
Age
In an AAA there degeneration of what 3 things?
Smooth muscle
Elastic
Structure
In how many layers is there degeneration of smooth muscle, elastic and structural degeneration of in a true AAA?
All 3 layers of vascular tunic (intima, media, adventitia)
What does pseudo aneurysm mean?
Not all 3 layers (intima, media an adventitia) are affected by degeneration of smooth muscle, elastic and structure.
What is the pathology of an AAA?
Smooth muscle, elastic and structural degeneration in all 3 layers of the vascular tunic with leukocyte infiltrate
How dilated is an AAA for a severe risk of rupture?
5.5+ cm
An AAA rupture is a s_____ e______
surgical emergency
What type of AAA may younger patients who smoke and have atherosclerotic plaques have?
Inflammatory AAA
What may younger patients who have an AAA also present with?
Pyrexia (fever)
What are symptoms of an AAA?
Asymptomatic until increased risk of rupture
Sudden epigastric pain radiating to flank
Pulsatile mass in abdomen
Hypotensive and tachycardic
What is a differential diagnosis for an AAA?
Acute pancreatitis
(Typically non-pulsatile and more associated with Grey Turner/ Cullen signs)
How is an AAA diagnosed?
Abdominal ultrasound
Why is an abdominal ultrasound a good diagnostic tool for an AAA?
Cheap
Easy
Sensitive and specific
What is treatment for a non-ruptured AAA?
Manage risk factors
Smoking cessation
Decreased BMI
Statins
Lower blood pressure
If less than 5.5 cm then monitor
What is treatment if symptomatic AAA or 5.5+ cm or expanding at a rate of 1 cm+ per year?
Consider surgery:
EVAR (endovascular repair) involving stent inserted via femoral or iliac artery
or open surgery
What is a benefit of EVAR over open surgery?
Less invasive
What is a disadvantage of EVAR over open surgery?
Most post-op complications
What happens if an AAA ruptures?
Stabilise ABCDE
Fluids and transfusion considered
Then surgery
AAA graft surgery (replace weakened walls with graft
Surgical emergency or will die
20% of AAA rupture where?
Anterior side (very bad)
80% of AAAs rupture where?
Retroperitoneal side (less bad)
Most AAAs occur in infrarenal aorta but can occur in t_____ aorta (often due to connective tissue disorders and atherogenesis)
thoracic
What is used to monitor an AAA in thoracic aorta?
CT or MRI
If any symptoms, surgery straight away
