Aortic aneurysm Flashcards
What is an abdominal aortic aneurysm?
DIlation of the abdominal aorta to >50% of normal diameter/ >,3cm, involving all 3 layers of the endothelium
What is the normal diameter of the infrarenal aorta in over 50s?
F: 1.5cm
M: 1.7cm
Describe epidemiology of AAA
Peak 60-70y
M > F
List 6 risk factors for AAA
SMOKING
HTN
FH
COPD
Coronary, cerebrovascular or PAD
Hyperlipidaemia
List 3 genetic condition associated with development of AAA
Ehlers Danlos
Marfans
Turners
Where do most AAA’s occur?
90% occur below renal arteries
(10% above)
What are the 2 shapes of AAA?
Fusiform (equally round)
Saccular (outpouching)
Describe the nature of AAA’s
Usually asymptomatic or have nonspecific Sx
Often discovered incidentally on US or CT
What may be found on examination in AAA?
Bruit on auscultation
Pulsatile, expansile mass in abdomen
What is the process for AAA screening?
In males >65y: single abdominal USS
<3cm = normal, no further action
If AAA:
3-4.4cm: small- rescan every 12m
4.5-5.5cm: medium- rescan every 3m
>5.5cm: 2ww to vascular for probable intervention
Give 2 features suggestive of low rupture risk in AAA. What should ongoing management be?
Asymptomatic
Diameter <5.5 cm (small + med)
USS surveillance + optimise cardiovascular RFs
Give 2 features suggestive of high rupture risk in AAA. What should ongoing management be?
Symptomatic
Diameter >5.5cm or rapidly enlarging >1cm/ year
2ww referral to vascular surgery
Treat with EVAR or open surgery
Give 3 risk factors for AAA rupture
Rapidly expanding
Large diameter
Smoking
What operations are used for AAA repair?
EVAR
Stent placed in abdominal aorta via femoral artery to prevent blood collecting in the aneurysm
Open replacement
If young (longer recovery time but lower chance of further procedures)
Give 1 complication of EVAR
Endo-leak: stent fails to exclude blood from the aneurysm
Usually presents w/o Sx on routine f/u
What can ruptured AAA present similarly to?
Renal colic
Loin to groin pain
What are 3 complications of AAA?
Rupture
Embolism (thrombotic material from aneurysm)
Aortic dissection
How can ruptured AAA present?
Catastrophic: sudden collapse
Sub-acute: persistent severe central abdo pain with developing shock
What is the mortality rate for ruptured AAA?
~80%
What is the classic triad of ruptured AAA?
Hypotension due to hypovolaemic shock
Sudden onset severe, tearing back or abdo pain with radiation to the flank, buttocks, legs, or groin
Painful pulsatile mass
Give 4 non-specific S/S of AAA rupture
Grey Turner +/or Cullen sign
N+V
Syncope (due to blood loss)
Haematuria
Describe diagnostics in unstable patients with suspected AAA
Clinical Dx
Do NOT delay dx + Mx while waiting for imaging
What is first line imaging in suspected AAA if not previously known to have AAA, is stable and this doesn’t delay intervention?
Aortic USS
What imaging is performed in haemodynamically stable patients with ruptured AAA?
CT angiogram
Confirms rupture + evaluates whether endovascular repair is feasible
Describe management of ruptured AAA
Urgent vascular review
Crossmatch 6 units blood
HD UNstable: clinical dx, send to theatre. If frail consider palliation
HD stable: CT angiogram if dx is in doubt + assess ability of endovascular repair
HD = Haemodynamically
Describe initial management of ruptured AAA
Large bore IV access
Start continuous monitoring
Immediate haemodynamic support (fluid resus, blood transfusion)
Aim for definitive Tx within 90 mins
Other than abdominal, what other aortic aneurysm can occur?
Thoracic aortic aneurysm
Where is the most common site for thoracic aortic aneurysms?
Ascending aorta
How may TAA’s present?
Most asymptomatic
If symptomatic: chest pressure, thoracic back pain, features of mediastinal compression e.g. difficulty swallowing
What is the best confirmatory test for TAA’s?
CT angiography
Describe management of TAA
All: reduction of cardiovascular RFs
Asymptomatic: surveillance + elective repair
Symptomatic + Ruptured: repair
What are the approaches to surgical repair of TAA’s?
Open surgical repair (OSR): ascending aorta + aortic arch
Thoracic endovascular aneurysm repair (TEVAR) or OSR: descending/ thoracoabdominal aneurysms
Describe management of cardiovascular risk factors in TAA’s
BP Mx: reduce aortic wall stress- BB, ACEi, ARBs
Smoking cessation
Lipid profile optimisation: statins
