Arteriosclerosis

Question 1

What is arteriosclerosis?

Answer 1

general term for “hardening”, thickening and loss of elasticity, of arteries

3 subtypes:

• arteriolosclerosis
• atherosclerosis
• Mönckeberg medial sclerosis

Question 2

What is arteriolosclerosis?

(cause and affected vessels)

Answer 2

caused by hypertension

effects small arteries/arterioes

can be either:

• hyaline arteriosclerosis (chronic, benign HTN)
• hyperplastic arteriolosclerosis (malignant HTN)

Question 3

What is atherosclerosis?

(cause and affected vessels)

Answer 3

caused by atheromatous plaque formation

effects large/medium arteries

Question 4

What are risk factors of atherosclerosis?

Answer 4

Non-modifiable:

• genetic/family history
• age
• male > post-menopausal women (estrogen is protective) >> pre-menopausal women

Modifiable:

• metaboic syndrome/components (hyperlipidemia, HTN, DM, obesity)
• smoking

-low HDL/high LDL

• inactivity
• competitive/stressful life style
• inflammation
• hyperhomocysteinemia

Question 5

What are the mechanisms by which atherosclerosis causes clinical manifestations?

Answer 5

• wall weakening -> aneurysm or rupture
• plaque rupture -> thrombosis/embolization
• plaque growth -> stenosis

Question 6

What are complications of atherosclerosis?

Answer 6

• vascular dementia (cerebral As.)
• cerebral infract/hemorrhage
• ishcemia, fibrosis, MI (coronary As.)
• stenosis/aneurysm/rupture
• hypertension (extrarenal)
• uremia & HTN (intrarenal)
• peripheral vascular disease -> occlusion -> gangrene

Question 7

How doe atheromatous plaques form?

Answer 7

• endothelial injury ->
• > endothelial activation (PDGF, FGF, TGF-α)
• > infiltration of monocytes/macrophages & smooth muscle proliferation
• > accumulation of lipids; foam cells -> fatty streak formation (first gross finding on vessel)
• >

Question 8

What is the structure of an atheromatous plaque?

Where in the vessel wall do they form?

Answer 8

• fibrous cap formed by smooth muscle cell proliferation and inflammatory cells
• necrotic center of foam cells and cholesterol

Forms internal to the internal elastic membrane; within the tunica intima

Question 9

What is Mönckeberg medial sclerosis?

Answer 9

calcificaition of the internal elastic membrane

• normal finding that increases with age
• no narrowing of lumen -> clincially benign