Aortic Aneurysm & Aortic Dissection (pathology)

Question 1

What is an aortic aneurysm? What % increase in diameter of blood vessel is required?

Answer 1

Localised enlargement of artery caused by weakening of vessel wall

50% increase in diameter of blood vessel
- Normal Aorta 2 cm —> aneurysm= 3cm or more

Question 2

What is a true and false aneurysm?

Answer 2

True aneurysm:
- Involves all 3 layers of aorta
False/pseudoaneurysm:
- Rapture in the vessel wall —> blood leaks out and pools

Question 3

What are the risk factors for an aneurysm (5)?

Answer 3

• Male of European descent
• Age
  
  • Ultrasound screening programme for males >65 years
• Hypertension
• Smoking
• Hyperlipidaemia

Question 4

What are the additional risk factors for thoracic aortic aneurysm (6)?

Answer 4

• Bicuspid aortic valve
• Coarctation (narrowing of aorta near ligamentum arteriosum)
• Marfan’s syndrome
• Ehlers’s Danlos syndrome
• Tertiary syphilis
• Takayasu’s arteritis (granulomatous vasculitis)

Question 5

What are the signs/symptoms of aneurysm (7)?

Answer 5

• Asymptomatic —> identified through CT, X-ray
• SOB – associated with aortic regurgitation
• Dysphagia and hoarseness
• Back pain
• Sharp pain radiating to back (between scapulae)
• Hypotension
• Pulsatile mass

Question 6

What are the investigations for an aneurysm?

Answer 6

• CXR —> widened mediastinum
• Echo —> aortic root size and aortic valve
• CT angiogram aorta-diagnostic
• MRI aorta
  
  • diagnostic + follow up

Question 7

What are the treatment/management options for aneurysms?

Answer 7

Repair:

• Open repair —> most common for raptured aneurysm
  
  • Large laparotomy - clamp below iliac a.
• Endovascular repair —>stent to bypass blood flow through aneurysm (preferred if good anatomy)

Medical:
- hypertension control

Question 8

What are the criteria for surgery on aneurysm?

Answer 8

• Aneurysm > 5 cm, 0.5 cm growth/ in six months – symptomatic
• > 5.5 cm- Emergency
• 4.5-5.5 cm= 6 M/3M review

Question 9

What is an aortic dissection?

Answer 9

Tear in the intimal layer of the aorta

- Cystic medial necrosis= replacement of media with mucopolysaccharide

Question 10

How is an aortic dissection classified?

Answer 10

Stanford – Most used!

• Type A —> involving ascending aorta - often FATAL
• Type B —> not involving ascending aorta - less severe because adventitia of descending aorta is tougher

Question 11

What are the risk factors for aortic dissection (5)?

Answer 11

• Hypertension
• Atherosclerosis
• Marfan’s syndrome
• Bicuspid aortic valve
• Trauma

Question 12

What are the symptoms of aortic dissection?

Answer 12

• Chest pain:
  
  • severe, sharp, interscapular
• Collapse due to tamponade, acute aortic regurgitation, external rapture
• Stroke (carotid artery involved)

Question 13

What are the signs of aortic dissection?

Answer 13

• Reduced/ absent peripheral pulses
• Hypertension or hypotension
• BP mismatch
• Murmur of aortic regurgitation (early diastolic)
• Pulmonary oedema
• Signs of stroke

Question 14

What are the investigations for aortic dissection?

Answer 14

• ECG
  
  • ST elevation/ischaemia if carotid involved
• CXR
  
  • widened mediastinum
• Transthoracic echo (TTE)
  
  • assess aortic root
• CT angiogram aorta – DIAGNOSTIC

Question 15

What is the treatment/management for Type A aortic dissection?

Answer 15

-	Blood pressure control (IV)
	•	Beta blocker 
	•	CCB 
	•	Nitrate 
	•	Sodium nitroprusside 
-	Emergency surgery

Question 16

What is the treatment/management for Type B aortic dissection?

Answer 16

Conservative management:

• Blood pressure control (same as type A)
• Percutaneous (endovascular) intervention
  
  • If expanding, rapture or branch involvement causing ischaemia