Cardiology- AAA Flashcards
what is an abdominal aortic aneurysm?
an AAA refers to the dilation of the abdominal aorta with a diameter of more than 3 cm. often the first time patients become aware of an aneurysm is when it ruptures, causing life threatening bleeding into the abdominal cavity. the mortality of a ruptured AAA is around 80%
which demographic is an AAA most commonly found in?
most common in males
usually 70+ yrs old
what is the normal aortic diameter?
2cm
what are the risk factors for AAA?
- male gender
- female gender (higher risk of rupture, not occurance)
- atheroslcerosis
- smoking
- COPD (likely a reflection of smoking history)
- age (increasing)
- hypertension
- family history
what is a protective risk factor of AAA?
how?
Diabetes
the high blood sugar associated with diabetes can cause damage to the arterial walls and make them stiffen. the stiffness of the arterial walls can make them less prone to expansion and rupture.
what is the pathophysiology of AAA?
the inflammation and degradation of smooth muscle cells causes the loss of the structural integrity of the aortic wall. this leads to the widening of the vessel. mechanical stress (e.g. hypertension) acts of the weakened wall tissue and leads to dilation and rupture.
what other problems can AAA lead to?
dilation of the vessels may disrupt the laminar flow and turbulence causing thrombi formation in the aneurysm and thromboembolism.
what are the symptoms of AAA?
most AAAs are asymptomatic so symptoms only present when it ruptures
* severe abdominal pain (can radiate back to groin)
* hemodynamic instability (hypotension and tachycardia)
* pulsatile and expansile mass in the abdomen
* collapse and loss of consiousness
* death
what are some signs of AAA?
may be detected on routine screening or when it ruptures. can be an incidental finding on an abdominal xray, ultrasound or CT scan
* grey turner’s sign (ruptured AAA, bruising on the flanks)- also seen in acute pancreatitis.
* Cullen’s sign: pre-umbilical bruising
what are the 1st line of investigations to be carried out of AAA is suspected?
ultrasound- confirms diagnosis, used in screening of age 65+
what is the gold standard investigation for AAAs?
CT angiogram- provides a more detailed picture than an ultrasound, helps guide surgery to repair the aneurysm.
what are the classifications of AAAs?
normal: less than 3cm
small aneurysm: 3cm - 4.4cm
medium: 4.5cm to 5.4cm
large: above 5.5 cm
what are the different types of AAAs?
Inflammatory AAA- type of AAA that can affect younger patients and is associated with smoking, atherosclerosis and vasculitis
thoracic AAA- typially a symptom of Marfan syndrome or Ehler- Danlos syndrome (connective tissue disorders) and atherogenesis.
which ways can AAAs rupture and how does this affect their prognosis?
20% rupture anteriorly
80% rupture posteriorly
posteriorly ruptured AAAs have a better prognosis.
what are the different types of management for AAAs?
treat reversible risk factors to prevent progression
monitor the patients
how do you treat the reversible risk factors for AAA?
stop smoking
healthy diet and exercise
optimise management of hypertension, diabetes and hyperlipidemia
how do you monitor patients with AAA?
yearly scans for patients with small aneurysms (3cm - 4.4cm)
3 monthly scans for patients with medium aneurysms (4.5cm - 5.4cm)
what is the treatment for patients with AAA?
elective surgery- open surgery or endovascular aortic repair (EVAR)
who classifies for the elective repair of AAAs?
patients with a symptomatic aneurysm/ diameter growing more than 1cm per year/ diameter above 5.5cm
who is offered screening for AAA?
all men over 65
women over 70 with risk factors
what are the complications of an AAA?
- ruptured aneurysm
- thrombosis
- embolism
- abdominal compartment syndrome (increased pressure in the abdomen)
