Atherosclerosis

Question 1

When does intimal thickening happen

Answer 1

because of injury and aging

Question 2

Atherosclerosis

Answer 2

hardening of arteries. Specifically fibrofatty lesion in tunica intima which protrude into vascular lumen, weaken tunica media

Question 3

What does obstruction of vascular lumen lead to

Answer 3

ischemia, infaration - which can lead to development of aneurysm

Question 4

How does smooth muscle get into the sub-endothelial compartment

Answer 4

• from tunica media through fenestrations

- precursor cells in blood that squeeze between damage in injury

Question 5

How do foam cells form

Answer 5

• LDL in subendothelial compartment
• becomes oxidized
• phagocytosed by macrophages and smooth muscle cells

Question 6

fatty streaks

Answer 6

early changes to tunica intima, but not to level of atheroma

Question 7

How can you tell if it’s a fatty streak (microscopic view)

Answer 7

thickening of intima
separation from internal elastic membrane
foam cells

Question 8

Atherosclerotic lesions

Answer 8

dark deposits that become calicified, are non reversible

Question 9

Non-modifiable risks for atherosclerosis

Answer 9

40-60 yo
family history
male
genetic abnormalities

Question 10

Modifiable risks for atherosclerosis

Answer 10

hyperlipidemia
cigarettes
c-reactive protein
hypertension
diabetes

Question 11

Normal total cholesterol

Answer 11

<200 mg/dl

Question 12

Normal LDL

Answer 12

<130 gm/dl

Question 13

Normal HDL

Answer 13

> 45 mg/dl

Question 14

Normal triglycerides

Answer 14

<150 mg/dl

Question 15

How does c-reactive protein put you are more risk

Answer 15

• endothelial cells become prethrombotic
• increase their adhesiveness for WBC
• causes inflammation of wall vasculature

Question 16

What has to happen to cause endothelial cell dysfunction

Answer 16

some injurious event - can be chronic endothelial injury like hyperlipidemia, hypertension, etc

Question 17

Endothelial dysfunction

Answer 17

increased permeability, leukocyte adhesion

Question 18

Key events of atherosclerosis

Answer 18

1) Chronic endothelial injury
2) Endothelial dysfunction
3) Smooth muscle recruitment to intima. Macrophage activation
4) Macrophages and smooth muscle cells engulf lipid
5) Smooth muscle proliferation, collagen and other ECM deposition, extracellular lipid

Question 19

Foam cells

Answer 19

smooth muscle cells or macrophages. Macrophages predominant form

Question 20

Role of NO in adhesion

Answer 20

prevent adhesion of leukocytes to endothelium, reduce adhesion of platletes

Question 21

Frequencies of critical stenosis of cornoary arteries (most to least common)

Answer 21

1) anterior interventricular branch of left coronary artery
2) Right coronary artery
3) Circumflex branch of left coronary a

Question 22

Wavefront phenomenon of necrosis

Answer 22

necrosis happens inner layer of myocardium then outer myocardium

Question 23

What does triphenyltetrazolium chloride do

Answer 23

stains viable cells red and nonviable white

Question 24

What are the consequences of myocardial ischemia and infarction

Answer 24

arrythmia
acute rupture of cardiac wall of IV septum
rupture of papillary muscles
ventricular aneurysm

Question 25

Order of events in cerebral infarction

Answer 25

1) Intense eosinophilia (12-24 hours)
2) neutrophils invade to clean up damage
3) macrophages come in and cause proliferation of glial cells (10 days)