Diseases of the Aorta (Corbett) - 11/2/16

Question 1

What is Fibrillin-1?

Function?

Deficiency?

Answer 1

Glycoprotein that helps to maintain structural integrity of aortic wall and valve leaflets

Function: tether VSMCs to matrix of elastin and collagen

Deficiency: VSMC detachment from elastin and collagen (loss of ECM structural integrity)

Marfan Syndrome

Question 2

Typical Anatomy of the Aorta

Answer 2

Question 3

How common is it to have a variation in aortic arch anatomy?

Answer 3

25% (1 out of 4)

Question 4

Bicuspid aortic valve

BAV is associated with __________.

Answer 4

Disease (usually congenital) of the aortic valve, in which two of the aortic valvular leaflets fuse during development

RESULT: valve is bicuspid, instead of the normal tricuspid configuration.

BAV is associated with aortic root dilation.

(ARD inc. risk of acute aortic dissection or rupture)

Question 5

What is coarctation of the aorta?

Answer 5

Congenital birth defect in which part of the aorta is narrower than usual

Question 6

Classical findings of coarctation (3)

Answer 6

Older child and adult

1. Systolic HTN in upper extremities
2. Reduced systolic BP in lower extremities
3. Radial artery to femoral pulse delay

Question 7

Aortic Dissection

Answer 7

Intimal tear and high pressure allows blood to gain access to media layer (forming a false lumen)

Question 8

Classification of Aortic Dissection

Answer 8

Stanford A (proximal)

Stanford B (Distal)

Question 9

Clinical Presentation of Acute Dissection

Key Exam Findings

Answer 9

Clinical Presentation

• Chest pain (90%) of severe intensity (90%) that occur suddenly (84%)
• Sharp/tearing
• Radiates to back

Key Exam Findings

• HTN on presentation
• Aortic regurg murmur

Question 10

Aortic Aneurysm

Answer 10

Localized pathologic dilatation of the aorta - diameter at least 50% greater than normal size

In abdominal aorta: > 3 cm

May cause abdominal and/or back pain, which is a sign of:

• leaking
• dissection
• imminent rupture

Question 11

Aortic aneurysm (two main types)

Answer 11

Abdominal aortic aneurysm

• Associated with atherosclerosis
• Risk factors: hx of tobacco use, inc. age, male sex, family hx
• May present as palpable pulsatile abdominal mass

Thoracic aortic aneurysm

• Associated with cystic medial degeneration/necrosis
  
  • Disorder of large arteries, in particular the aorta
  • Characterized by accumulation of basophilic ground substance in the media with cyst-like lesions
• Risk factors: HTN, bicuspid aortic valve, connective tissue disease (Marfan Syndrome)
• Historically associated with tertiary syphilis and turner syndrome

Question 12

Traumatic aortic rupture

Signs and symptoms

Answer 12

Due to trauma and/or deceleration injury, most commonly at aortic isthmus (proximal descending aorta just distal to origin of left subclavian artery)

• site of ductus arteriosus

Sudden onset of abdominal OR back pain + hypotension = ruptured AAA

S&S: hypotension; cold, clammy extremities; other signs of shock