Morris- Acute Coronary Syndromes

Question 1

What comprises intima

Answer 1

1. single layer of endothelial cells
2. underlying ECM
3. Smooth muscle cells

Question 2

what is the role of endothelial cells

Answer 2

1. physical barrier
2. receives and transmits biochemical physcial information bidirectionally
3. regulates blood flow

Question 3

what is the first step in the formation of atherosclerotic plaques

Answer 3

• fatty streaks (looks like butter on the endothelium)

Question 4

describe positive remodeling

Answer 4

aka lumen area compensation

• start with normal vessel (endothelium and lumen); first you get fatty streaks, then plaque build up… however, it’s all external… NO LUMEN SPACE COMPROMISE

Question 5

with positive remodeling/lumen area compensation, would you have angina?

Answer 5

• NO

Question 6

what is negative remodeling

Answer 6

lumen area is compensated… you get angina

Question 7

What is the signal event in acute coronary syndrome?

Answer 7

• fissuring or rupture of an atherosclerotic plaque

Question 8

name four factors that contribute to plaque vulnerability

Answer 8

1. large lipid core
2. Thin cap
3. high macrophage content (more inflammatory responses so more protleotyic enzymes)
4. low smooth muscle cell count

Question 9

what is the effect of high shear on the arteries with ACS

Answer 9

• promotes arterial thrombosis

Question 10

Name three characterizations of plaques

Answer 10

1. quiescent… there is a plaque but percents stenosis is large enough so that its stable
2. Fibrotic/scarred plaque… plaque is enlarged but not ruptured… develop stable angina because it starts predictably and ends predictably
3. Vulnerable/ruptured plaque (causes MI, sudden death)

Question 11

Name Unstable syndromes that fall under acute coronary syndromes

Answer 11

1. unstable angina
2. NSTEMI myocardial infarction
3. STEMI myocardial infarction
4. sudden death

Question 12

what is role of platelets in ACS

Answer 12

• try to aggregate at the site of rupture; these activated platelets attract other platelets, and we get a thrombus

Next, you get the coagulation cascade to try to make this thrombus established, making it creep into vessel

Question 13

what does the ST elevation indicate on EKG

Answer 13

• angina

Question 14

T/F, if you have no ST elevation, you can’t have MI

Answer 14

False… NSTEMI

Question 15

T/F if you have unstable angina you’ve lost myocardial muscle

Answer 15

• FALSE

Question 16

why might an arteriogram on a patient with atherosclerosis seem normal

Answer 16

• positive arterial remodeling