13 - Atheroma, Thrombosis and Embolism

Question 1

Commonly affected vessels for atherosclerosis

Answer 1

Bifurcations
Ab aorta
Coronary arteries
Popliteal arteries
Carotid vessels
Circle of willis

Question 2

Atherosclerosis - pathophysiology

Answer 2

1. endothelial injury
2. hyperlipidaemia accumulation
3. monocytes migrate and ingest lipid forming foam cells (fatty streak)
4. foam cells secrete chemokines
5. smooth cell proliferate and secrete connective tissue
6. atherosclerotic plaque formed

Question 3

Causes of endothelial injury

Answer 3

haemodynamic injury
chemicals
immune complex deposition
irradiation

Question 4

what is it that attracts monocytes to the intima?

Answer 4

the lipids and endothelial injury cause release of VCAM1

Question 5

Which wall of artery is this happening in?

Answer 5

Intima

Question 6

Platelets what are they?

Answer 6

Fragments of megakaryocytes in the bone marrow that circulate in blood

Question 7

What do platelets bind to?

Answer 7

Collagen exposed by endothelial damage and become activated

Question 8

What do platelets secrete?

Answer 8

Alpha granules - fibrinogen, fibronectin, PDGF

Dense granules - chemotactic chemicals

Question 9

Virchow’s triad

Answer 9

To do with platelet adhesion and thrombus formation…

Changes in intimal surface of vessel
Pattern of blood flow
Blood constituents

Question 10

Venous thrombosis in relation to virchow’s triad

Answer 10

Valve problems
immobile blood flow
More inflammatory mediators (infection, malignancy)
FV leiden
Oestrogen

Question 11

Gas emboli

Answer 11

Air - >100ml for effects - obstetric procedures/chest wall injury

Nitrogen - the bends, divers, tunnel workers, nitrogen bubbles enter bones, joints and lungs