Aortic dissection Flashcards Preview

Y3 - Conditions and prodedures > Aortic dissection > Flashcards

Flashcards in Aortic dissection Deck (8)
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1
Q

Define

A
  • A condition where a tear in the aortic intima allows blood to surge into the aortic wall, causing a split between the inner and outer tunica media, creating a false lumen
  • Medical emergency
2
Q

What are the two types?

A

o Type A: ASCENDING aorta (MOST COMMON)

o Type B: DESCENDING aorta (distal to the left subclavian artery)

3
Q

What’s the aetiology?

A

• Aortic dissection is usually preceded by degenerative changes in the smooth muscle of the aortic media

4
Q

What are the risk factors?

A

• Common causes and risk factors:
o HYPERTENSION
o Aortic atherosclerosis
o Connective tissue disease (e.g. Marfan’s, Ehlers-Danlos, SLE)
o Congenital cardiac abnormalities (e.g. coarctation of the aorta)
o Aortitis
o Iatrogenic (e.g. during angioplasty/angiography)
o Trauma
o Crack cocaine
• NOTE: expansion of the false lumen can lead to obstruction of the subclavian, carotid, coeliac and renal arteries
o Hypoperfusion of the target organs of these major arteries can give rise to other symptoms (e.g. carotid artery –> collapse)

5
Q

Epidemiology?

A

• Most common in males aged 40-60 yrs

6
Q

What are the presenting symptoms?

A

• MAIN SYMPTOM: sudden central ‘tearing’ pain, it may radiate to the back in between the shoulder blades (it can mimic MI)
• Other symptoms caused by obstruction of branches of the aorta:
o Carotid artery –> hemiparesis, dysphasia, blackout
o Coronary artery –> chest pain (angina or MI)
o Subclavian artery –> ataxia, loss of consciousness
o Anterior spinal artery –> paraplegia
o Coeliac axis –> severe abdominal pain (due to ischaemic bowel)
o Renal artery –> anuria, renal failure

7
Q

What are the signs?

A
•	Murmur on the back (below the left scapula), descending to the abdomen 
•	Hypertension
•	Blood pressure difference between the two arms > 20 mm Hg
•	Wide pulse pressure 
•	Hypotension may suggest tamponade 
o	Check for pulsus paradoxus = abnormally large decrease in systolic blood pressure and pulse wave amplitude during inspiration
o	This may indicate:
•	Tamponade
•	Pericarditis
•	Chronic sleep apnoea
•	Obstructive lung disease 
•	Signs of Aortic Regurgitation
o	High volume collapsing pulse 
o	Early diastolic murmur over aortic area 
•	Unequal arm pulses 
•	There may be a palpable abdominal mass
8
Q

What are the appropriate investigations?

A
•	Bloods
o	FBC
o	X-match 10 units of blood (prep for surgery)
o	U&E - check renal function 
o	Creatinine – check renal function
o	Clotting screen
o	Cardiac enzymes
•	CXR

o Widened mediastinum
• ECG
o Often NORMAL
o ST depression may occur with acute dissection
o If the ostia of the right coronary artery is compromised you may get signs of:
• Left ventricular hypertrophy
• Inferior MI

• CT Thorax, abdomen and pelvis

o	Shows false lumen
o	show extent of aneurysm
•	Echocardiography
o	Transoesophageal allows visualisation 
•	Cardiac catheterisation and aortography