Arterial thrombosis

Question 1

Outline the process of atherosclerosis (3)

Answer 1

Endothelial damage
Recruitment of cholesterol-rich macrophages, forming plaques
Calcification forms stable plaques

Question 2

Risk factors for arterial thrombosis (4)

Answer 2

Hypertension
Smoking
High cholesterol
Diabetes mellitus

Question 3

Chemicals secreted by platelets which induce activation (2)

Answer 3

ADP

Thromboxane A2

Question 4

Mechanism of action of aspirin

Answer 4

Inhibits COX (necessary to produce thromboxane A2)

Question 5

Side effects of aspirin related to its mechanism (2)

Answer 5

Bleeding- reduced platelet aggregation

GI ulceration- reduced prostaglandins, hence greater acid production

Question 6

Mechanism of clopidogrel/prasugrel

Answer 6

ADP receptor antagonists

Question 7

Mechanism of dipyridamole

Answer 7

PDE inhibitor- reduced production of cyclic AMP, a key second messenger in platelet activation

Question 8

Mechanism of abciximab

Answer 8

GPIIb/IIIa inhibitors- prevent platelet aggregation

Question 9

When should anti-platelet agents be stopped prior to surgery?

Answer 9

7-10 days prior to surgery