Blood vessel sclerosis

Question 1

Types of sclerosis

Answer 1

1. Monckeberg’s medial calcific sclerosis
2. Atherosclerosis
3. Arteriosclerosis

Question 2

Monckeberg’s medial calcific sclerosis

Answer 2

Clinically insignificant
• age > 50 years
• Involves tunica media and internal elastic lamina
• Dystrophic calcification

Question 3

Stains for calcium

Answer 3

1. Vin Kossa

2. Alizarin red stain

Question 4

Arteriosclerosis

Answer 4

Thickening or hardening of arteries
Two types:
1. Hyaline:
 Benign HTN, DM
2. Hyperplastic:
 Malignant HTN

Question 5

Hyaline arteriosclerosis

Answer 5

• Seen in patients with benign HTN, DM

* Pink, homogenous, glassy appearance of arterial wall

Question 6

Hyperplastic arteriosclerosis

Answer 6

• Seen in patients with malignant HTN
• Hyperplasia of wall: smooth muscle proliferation
• Concentric laminated thickening ➡️ onion skin appearance on microscopy
• Fibrinoid necrosis can also be seen (malignant HTN)

Question 7

Risk factors of atherosclerosis

Answer 7

1. Non-modifiable
2. Modifiable
3. Additional:
   • infections: CMV, chlamydia, herpes
   • lipoprotein (a, apo B-100, apo A)
   • metabolic syndrome
   • hyperhomocysteinemia

Question 8

Non modifiable risk factors of atherosclerosis

Answer 8

1. Age
2. Male gender
3. Family history
4. Type A personality

Question 9

Modifiable risk factors for atherosclerosis

Answer 9

1. Sedentary lifestyle
2. Obesity
3. Hypertriglyceridemia
4. DM/ HTN
5. Smoking

Question 10

Pathogenesis of atherosclerosis

Answer 10

1. Vascular endothelial injury
2. Accumulation of LDL and its oxidised form
3. Monocyte adhesion
4. Smooth muscle migration from tunica media to intima and proliferates
5. Neo-intimal hyperplasia
6. Formation of atheromatous plaque

Question 11

Fatty streak

Answer 11

Earliest lesion of atherosclerosis

1 mm yellowish lesion

Question 12

Components of a atheromatous plaque

Answer 12

1. Fibrous cap & shoulder:
• Smooth muscle cells
• Macrophages, foam cells,
• Lymphocytes
• Collagen, elastin, proteoglycan, neovascularisation
2. Necrotic centre:
• Cell debris
• Cholesterol crystals
• Foam cells
• Calcium

Question 13

Types of plaque

Answer 13

1. Stable:
 Fibrous cap forms most of the plaque 
2. Vulnerable (unstable):
 Necrotic court forms most of the plaque
 More dangerous

Question 14

Complications of plaque

Answer 14

A. Aneurysm
C. Calcification 
U. Ulceration
T. Thrombosis
E. Embolism

Question 15

Vessels affected by atherosclerosis in descending order

Answer 15

1. Abdominal aorta (M/C affected)
2. Coronary artery
3. Popliteal artery
4. Descending thoracic aorta
5. Circle of Willis (least commonly affected)

Question 16

Aneurysm

Answer 16

Building/ dilation of a vessel wall
M/C of aortic aneurysm: atherosclerosis
Two types:
1. True:
 Involves all 3 layers of blood vessel
2. Pseudo/false:
• Due to extra vascular hematoma communicating with the vessel lumen
• M/C post MI rupture

Question 17

Leutic aneurysm/ syphilitic aneurysm

Answer 17

Occurs in tertiary syphilis
Usually affects ascending aorta and vasa vasorum
Tree bark appearance like lung histoplasmosis

Question 18

Mycotic aneurysm

Answer 18

Caused by Staphylococcus aureus

Occurs in femoral artery