Aortic Dissection

Question 1

Aortic Dissection- Definition

Answer 1

• 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

Question 2

Aortic Dissection- Risk Factors

Answer 2

• Preceded by degenerative changes in the smooth muscle of the aortic media
• HYPERTENSION
• Connective tissue disease
• Congenital cardiac abnormalities
• Aortitis
• Iatrogenic (e.g. during angioplasty/angiography)
• Trauma
• Crack cocaine

Question 3

Aortic Dissection- Epidemiology

Answer 3

• Males

* 40-60 yrs

Question 4

Aortic Dissection- Symptoms

Answer 4

• Sudden, central ‘tearing’ pain, may radiate to the back between shoulder blades
• Other symptoms due to obstruction of branches of aort:
o Carotid -> hemiparesis, dysphagia, blackout
o Coronary -> chest pain
o Subclavian -> ataxia, LOC
o Anterior spinal artery -> paraplegia
o Coeliac axis -> severe abdominal pain
o Renal artery -> anuria, renal failure

Question 5

Aortic Dissection- Signs on Exam

Answer 5

•	Murmur on back, descending to abdomen
•	Hypertension
•	Blood pressure difference between rms >20mmHg
•	Wide pulse pressure
•	Hypotension may suggest tamponade
o	Check for pulsus pardoxus  abnormally large decrease in SBP and pulse wave amplitude during inspiration
o	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
•	Palpable abdominal mass

Question 6

Aortic Dissection- Investigations

Answer 6

•	Bloods
o	FBC
o	X-match 10 units
o	U&E- check renal function
o	Clotting screen

• CXR
o Widened mediastinum

•	ECG
o	Often normal
o	If opening of RCA is compromised, signs of:
	Left ventricular hypertrophy
	Inferior MI

• CT thorax
o False lumen

• Echo
o Transoephageal allows visualisation
• Cardiac catheterisation and aortography