Aortic Dissection

Question 1

Define:

Answer 1

A tear in the tunica intima which allows bloof to surge into the aortic wall ; causing the inner and outer tunica intima to split.

This creates a false lumen

Question 2

Aetiology:

Answer 2

Preceded by degenerative changes of the smooth muscle in the aortic wall

Question 3

Risk factors:

Answer 3

HYPERTENSION

Aortic atherosclerosis

Connective tissue disorders (Ehler’s Danlos, Marfan’s and SLE)

Congenital cardiac abnormlaities

Aortitis

Iatrogenic (after an angioplasty)

Trauma

Crack cocaine

Question 4

Symptoms

Answer 4

SUDDEN CENTRAL TEARING CHEST PAIN RADIATING TO THE BACK BETWEEN THE SCAPULAS.

If there is compromise on other arteries:

• Carotid = hemiparesis, dysphasia and blackout
• Renal = anuria and renal failure
• coronary = chest pain
• subclavian = ataxia + loss of consciousness
• Anterior spinal = paraplegia
• coeliac axis = severe abdo pain due to bowel ischaemia.

Question 5

Signs:

Answer 5

Murmur at the back below the left scapula

hypertension

Difference of >20 mmHg in BP of the arms

Wide pulse pressure

unequal arm pulses

palpable abdo mass

hypotension = tamponade

pulsus paradoxus - a paradoxical rise in JVP on inspiration –> in tamponade, pericarditis, chronic sleep apnoea and obstructive lung disease.

May have signs of aortic regurg:

• High vol collapsing pulse
• Early diastolic murmur

Question 6

Investigations:

Answer 6

Bloods:

• FBC
• U + E’s (to check the renal function)
• Clotting
• X-match ten units of blood

ECG - usually normal except in right coronary compromise where there is LVH and inferior MI

Transoesophageal Echo - to visualise the dissection

CXR - will show widened mediastinum

CT thorax - false lumen