EXAM #1: ARTERIOSCLEROSIS

Question 1

What is the definition of arteriosclerosis?

Answer 1

“Hard arteries” due to thickening of the blood vessel wall

Question 2

What are the three sub-categories of arteriosclerosis?

Answer 2

1) Atherosclerosis
2) Arteriolosclerosis
3) Monckeberg medial calcific sclerosis

Question 3

What is the definition of Atherosclerosis?

Answer 3

INTIMAL plaque that obstructs blood flow

Question 4

Describe the composition of an atherosclerotic plaque.

Answer 4

• Necrotic lipid core (cholesterol)
• Fibromuscular cap

*Often undergoes dystrophic calcification

Question 5

What vessels are most commonly involved in atherosclerosis?

Answer 5

Large and medium sized arteries i.e.

1) Abdominal aorta
2) Coronary artery
3) Popliteal artery
4) Internal carotid artery

Question 6

What are the modifiable risk factors in atherosclerosis?

Answer 6

1) HTN
2) Hypercholesterolemia (LDL)
3) Smoking
4) DM
- Inactivity
- Stress
- Obesity

Note that these risk factors are synergistic/ additive

Question 7

What are the nonmodifiable risk factors in atherosclerosis?

Answer 7

1) Age
2) Gender
- Males
- Post-menopausal women (estrogen is protective)
3) Genetics

Question 8

What total serum cholesterol increases the risk of atherosclerosis?

Answer 8

160 mg/dL

Question 9

Which familial dyslipoproteinemias are associated with premature atherosclerosis?

Answer 9

1) Familial hypercholesterolemia (increased LDL)
2) Familial combined hypercholesterolemia (Increased LDL and VLDL)
3) Familial Type III Lipoproteinemia (IDL)
4) Familial hypertriglyceridemia (VLDL and TAG)
5) Familial AI/CII (no HDL)

Question 10

Which of the familial dyslipoproteinemia is associated with the most severe premature atherosclerosis?

Answer 10

Familial AI/CII i.e. lack of HDL

Question 11

What is the impact of smoking on the etiology of atherosclerosis?

Answer 11

Smoking= 200% risk

Smoking cessation= 1/2 of the prior risk

Question 12

What are the two “unusual” risk factors associated with atherosclerosis?

Answer 12

1) Homocystine

2) Chlamydia pneumonia

Question 13

Outline the pathogenesis of atherosclerosis.

Answer 13

1) Endothelial injury:
- Damage to endothelium allows LIPIDS to lead into INTIMA
2) Macrophage response
- Lipids are oxidized and consumed by macrophages–>foam cells
3) INFLAMMATION and healing
- Leads to deposition of ECM and proliferation of smooth muscle

Question 14

What cellular adhesion molecule is over-expressed in response to endothelial injury in the pathogenesis of atherosclerosis?

Answer 14

Vascular cell adhesion molecule-1 (VCAM-1)

Question 15

What receptor on macrophages allows them to take up lipids to form foam cells?

Answer 15

Scavenger receptors

Question 16

What recruits macrophages to sites of intimal injury from accumulated lipids?

Answer 16

Monocyte chemo-attractant protein 1 (MCP-1)

Question 17

What is the significance of foam cells in the intima?

Answer 17

1) Cause smooth muscle cell emigration from the media to the intima
2) Further secretion of cytokines for inflammatory response

Causes further macrophage activation

Question 18

What factor is highly implicated in the proliferation of smooth muscle cells in the pathogeneis of athersclerosis ?

Answer 18

PDGF

Question 19

What are the two morphologic stages of atherosclerosis?

Answer 19

1) Fatty streaks
2) Proliferative lesion
2) Atherosclerotic plaque, or “atheroma”

Question 20

What is a fatty streak?

Answer 20

Flat yellow lesions of the intima consisting of foam cells/ lipid laden macrophages

Question 21

What process do atherosclerotic plaques undergo?

Answer 21

Dystrophic calcification i.e. “hardening” of the artery

Question 22

Where do atherosclerotic plaques begin to develop? Why?

Answer 22

Adjacent to bifurcations b/c of the changes in blood flow in these regions

Shear stress= endothelial injury

Question 23

What are the major complications of atherosclerotic lesions?

Answer 23

1) Calcification
2) Hemorrhage
3) Rupture or ulceration
4) Thrombosis

Question 24

Why is rupture of an atherosclerotic plaque dangerous?

Answer 24

Substances exposed by the rupture induces thrombogenesis

Question 25

What are the implications of the strength of the fibromuscular cap of an atherosclerotic plaque?

Answer 25

Thickness is directly correlated with stability *The thicker the cap, the less likely it is to rupture and thrombose*

Question 26

What is the primary prevention for atherosclerosis?

Answer 26

Prevention with: 1) Statins 2) Anti-hypertensives 3) Aspirin to prevent clotting *Lifestyle modification is key to prevention*

Question 27

What is secondary prevention in atherosclerosis?

Answer 27

Treatment once an atherosclerotic plaque has ruptured i.e: 1) TPa 2) Angioplasty 3) CABG

Question 28

What is the primary cause of an abdominal aortic aneurysm?

Answer 28

Atherosclerosis

Question 29

Why does atherosclerosis predipose one to an abdominal aortic aneurysm?

Answer 29

- Atherosclerosis in the media increases the diffusion barrier to the media - Hypoxia from limited diffusion leads to atropthy and weakness of the vessel wall - Ballooning of the vessel occurs

Question 30

What is the ABPI?

Answer 30

Ankle Brachial Pressure Index *Comparison of ankle BP to arm BP

Question 31

What ABPI is considered abnormal?

Answer 31

Less than 0.9 *The lower the number, the worse the PVD

Question 32

What is the major complication of peripheral atherosclerosis? What patient population is this most common in?

Answer 32

Gangrene *DM

Question 33

What happens when there is a MI or ischemic CVA?

Answer 33

Atherosclerotic plaque rupture and thrombosis that: - Occludes coronary artery (MI) - Occludes the cerebral artery (CVA)

Question 34

What degree of stenosis must occur for there to be complications?

Answer 34

70%

Question 35

What is the Glagov coronary remodeling hypothesis?

Answer 35

- As the vessel lumen narrows, it will initially expand to compensate - Eventually the vessel will not be able to expand further *This point, where the vessel can no longer expand is when severe disease results*