Aortic dissections and aneurysms: Pathology review

Question 1

What is a true aortic aneurysm ?

Answer 1

It involves all the 3 vessel layers The tunica intima, media, adevenitia.

Question 2

What is psuedoaneurysm ?

Answer 2

It involves only the tunica intima.

Question 3

What is the most important risk factor for aortic aneurysm ?

Answer 3

Atherosclerosis

Question 4

What is the pathophysiology of aortic aneurysm ?

Answer 4

Chronic inflammation causes the release of Matrix metaloproteinases which degrade the extracellular matrix of the tunica media weakening the aortic wall.

Question 5

What is the most common location of the AAA?

Answer 5

below the renal arteries at the level of L2 because the abodminal aorta doesn’t have vasa vasorum which makes the aorta vulnerable to ischaemia.

Question 6

What are the classic risk factors for AAA?

Answer 6

Age >65
Male sex
Smoking
Family Hx of AAA

Question 7

When is AAA more likely to occur ?

Answer 7

When the AAA diameter is >5 cm

Question 8

What is the triad of AAA?

Answer 8

Sudden onset of lower back or flank pain, hypotension and pulsatile abdominal mass.

Question 9

What is the pathophysiology of thoracic aortic aneurysm ?

Answer 9

Cystic medial degneration.

Question 10

What are the risk factors for Thoracic aortic aneurysm ?

Answer 10

• HTN
• Bicuspid aortic valve
• Marfan syndrome.

Question 11

What is the pathophysiology of syphilitic aortic aneurysm ?

Answer 11

Thrombangitis oblitarense which is small vessel vasculitis of the vasa vasorum of the throacic aorta.

Question 12

What are the risk factors for aortic dissection?

Answer 12

• HTN and bicuspid aortic valve.
• Connective tissue disorder Marfan and Ehlar danolse syndrome.
• Amphetamines and cocaine.

Question 13

What is the pathological cause of aortic dissection in HTN ?

Answer 13

Hyline arteriosclerosis of the vasa vasorum causes weakness of the aortic wall leading to dissection.

Question 14

What is stanford type A and B aortic dissections?

Answer 14

• Type A originate from the sinuo-tubular junction of the initial portion of the aorta.
• Type B originate form the left subclavian artery and involve the descending aorta.

Question 15

What is the Tx difference b/w Stanford type A and B dissections ?

Answer 15

A is treated surgically due to the risk of cardiac tamponade. Whereas B may be treated with beta blockers such as Esmolol.

Question 16

What is the most common aetiology of traumatic aortic dissection ?

Answer 16

Decelerating injury during MVA. The most common site is the aortic isthmus adjacent to the ligamentum arteriosum.