Aortic Dissection

Question 1

Define Aortic Dissection?

Answer 1

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

Question 2

How do we classify Aortic Dissection?

Answer 2

Type A: Ascending Aorta (most common)

Type B: Descending Aorta (distal to the left subclavian artery)

Question 3

What is Aortic Dissection usually preceded by?

Answer 3

Degenerative changes in the smooth muscle of the aortic media

Question 4

What are the common causes and risk factors of Aortic Dissection?

Answer 4

Hypertension
Aortic Atherosclerosis 
Connective Tissue disease 
Congenital cardiac abnormalities (coarctation of the aorta)
Aortitis 
Iatrogenic (e.g. during angioplasty/angiography)
Trauma
Crack Cocaine

Question 5

What can expansion of the false lumen lead to?

Answer 5

Obstruction of the subclavian, carotid, coeliac and renal arteries

Question 6

What can the obstruction of these major arteries lead to?

Answer 6

Hypoperfusion of the target organs of these major arteries can give rise to other symptoms (e.g. carotid artery obstruction leads to collapse)

Question 7

What is the epidemiology of Aortic Dissection?

Answer 7

Most common in males aged 40-60 years

Question 8

What is the main presenting symptom of Aortic Dissection?

Answer 8

Sudden central ‘tearing’ pain, it may radiate to the back in between the shoulder blades (it can mimic MI)

Question 9

What are the other symptoms caused by?

Answer 9

Obstruction of branches of the aorta

Question 10

What symptoms are caused by obstruction of Carotid Artery in Aortic Dissection?

Answer 10

Hemiparesis
Dysphasia
Blackout

Question 11

What symptoms are caused by obstruction of Coronary Artery in Aortic Dissection?

Answer 11

Chest pain (angina or MI)

Question 12

What symptoms are caused by obstruction of Subclavian Artery in Aortic Dissection?

Answer 12

Ataxia

Loss of consciousness

Question 13

What symptoms are caused by obstruction of Anterior Spinal Artery in Aortic Dissection?

Answer 13

Paraplegia

Question 14

What symptoms are caused by obstruction of Coeliac Axis in Aortic Dissection?

Answer 14

Severe abdominal pain (due to ischaemic bowel)

Question 15

What symptoms are caused by obstruction of Renal Artery in Aortic Dissection?

Answer 15

Anuria

Renal Failure

Question 16

What are the signs of Aortic Dissection on physical examination?

Answer 16

Murmur on the back (below the left scapula), descending to the abdomen
Hypertension
Blood pressure difference between the two arms > 20 mm HG
Signs of Aortic Regurgitation
Unequal arm pulses
There may be a palpable abdominal mass

Question 17

What do we check for in Aortic Dissection?

Answer 17

Check for pulsus paradoxus

Question 18

What is pulsus paradoxus?

Answer 18

Abnormally large decrease in systolic bp and pulse wave amplitude during inspiration

Question 19

What does pulsus paradoxus indicate?

Answer 19

Tamponade
Pericarditis
Chronic Sleep Apnoea
Obstructive Lung Disease

Question 20

What are the signs of aortic Regurgiation?

Answer 20

High volume collapsing pulse

Early diastolic murmur over aortic area

Question 21

What investigation would you do for Aortic Dissection?

Answer 21

Bloods 
CXR 
ECG 
CT Thorax 
Echocardiography
Cardiac Catheterisation and aortography

Question 22

What bloods would we do for Aortic Dissection?

Answer 22

FBC
X-match 10 units of blood
U&E - check renal function
Clotting Screen

Question 23

What would we see on a CXR for Aortic Dissection?

Answer 23

Widened mediastinum

Question 24

What might we see on an ECG for Aortic Dissection?

Answer 24

Otften normal
If the ostia of the RCA is compromised you may get signs of:
- Left Ventricular Hypertrophy
- Inferior MI

Question 25

What would we see on a CT Thorax for Aortic Dissection?

Answer 25

Shows false lumen

Question 26

Why do we do a Echocardiography for Aortic Dissection?

Answer 26

Transoesophageal allows visualisation