Anti-Platelet Therapy

Question 1

What happens after damage to the endothelium in atherosclerosis formation?

Answer 1

Recruitment of foamy macrophages

Question 2

Describe a stable atherosclerotic plaque

Answer 2

Hyalinised and calcified

Question 3

What do unstable atherosclerotic plaques lead to?

Answer 3

MI
Unstable angina
Stroke

Question 4

What are platelets derived from?

Answer 4

Megakaryocytes

Question 5

Give risk factors for arterial thrombosis

Answer 5

HTN
Smoking
Cholesterol
DM

Question 6

How is diabetes a risk factor for arterial thrombosis?

Answer 6

high sugar levels in blood damage the endothelium

Question 7

Which actions of platelets are targeted by anti-platelet therapy?

Answer 7

Aggregation -specialist

Activation - mostly

Question 8

What is the mechanism of action of aspirin?

Answer 8

Inhibits COX

Question 9

Normally, what is the action of COX?

Answer 9

Enzyme needed to produce TXA2

Question 10

Why are GI ulcers a side effect of aspirin therapy?

Answer 10

Blocks prostaglandins and gives less protection to stomach lining

Question 11

In which conditions should aspirin use be avoided?

Answer 11

Asthma

Question 12

What is the role of ADP in formation of platelet plug?

Answer 12

Binds to P2Y12 receptors to send signals for platelets aggregation

Question 13

Which drugs antagonise ADP receptors?

Answer 13

Clopidogrel

Prasugrel

Question 14

How does dipyridamole work?

Answer 14

Inhibits PDE

Question 15

How does PDE work in formation of the platelet plug?

Answer 15

PDE activates cAMP which should act as a messenger to cause platelet aggregation

Question 16

Give an example of a glycoprotein IIb/IIIa receptor antagonist?

Answer 16

Abciximab

Question 17

How long before surgery should anti-platelets be stopped?

Answer 17

7-10 days

Question 18

In severe bleed, how are the effects of anti-platelets reversed?

Answer 18

Platelet transfusion