6

Question 1

Define atheroma

Answer 1

Accum of IC & EC lipids in intima and media of large n medium sized arteries

Question 2

Define atherosclerosis

Answer 2

Thickening n hardening of artery walls bc atheroma

Question 3

Define arteriosclerosis

Answer 3

Thickening n hardening or artery/arteriole walls bc hypertension / diabetes

Question 4

What are the 5 cellular events leading to Atherosclerosis?

Answer 4

1. Chronic Endothelial Injury
2. Endothelial Dysfunction (platelet adhesion / PDGF release) (Monocye accum in intima)
3. SMC emigrate from media –> intima
4. MAC + SMC engulf accum oxidised lipid –> Foam Cells
5. SMC prolif in response to cytokines / GF

Question 5

What is the Macroscopic appearance of atherosclerosis?

Answer 5

Plaque
In elastic arteries (aorta / carotid / iliac)
In large / medium sized muscular arteries (coronary / popliteal)

Question 6

What are the 3 stages of plaque dev?

Answer 6

1. Fatty streak
2. Simple plaque
3. Complicated plaque

Question 7

Describe the Fatty Streak stage of plaque dev

Answer 7

Lipid deposition in intima
Yellow / slightly raised
No blood flow disturbance

Question 8

Describe the Simple Plaque stage of plaque dev

Answer 8

Yellow / White / Raised
Around ostia
Turbulent blood flow
Enlarge + coalesce

Question 9

Describe the Complicated Plaque stage of plaque dev

Answer 9

Calcification
Thrombosis
Haemorrhage into plaque
In aorta: weak walls / aneurysm forms (bulge in vessel)

Question 10

What is the Early Microscopic appearance of atherosclerosis?

Answer 10

Foam cell accum
SMC prolif
EC lipid depos

Question 11

What is the Later Microscopic appearance of atherosclerosis?

Answer 11

Fibrosis
Necrosis
Damaged extended to media
Plaque fissuring (cracking) n rupture

Question 12

What are the effects of atherosclerosis?

Answer 12

1. IHD (bc reduced blood flow to myocardium)
2. Cerebral Ischaemia (TIA / Stroke)
3. Abdominal Aortic Aneurysm (AAA)
4. Peripheral Vasc Disease
5. Mesenteric Ischaemia (small intestines)

Question 13

How does a Cerebral Infarction (stroke) happen?

Answer 13

1. Atherosclerosis of Carotid Arteries
2. Thrombus forms over plaque
3. Thromboembolism to Cerebral Arteries

Question 14

How does an AAA happen?

Answer 14

1. Local dilation bc weakened wall
2. Arteries filled by thrombus
3. Can rupture / prod. emboli

Question 15

What cells are involved in atherogenesis?

Answer 15

1. Endothelial cells
2. Platelets
3. SMC
4. MAC

Question 16

What is the role of endothelial cells in atherogenesis?

Answer 16

Haemostasis
Collagen secretion
Stim SMC prolif + migration

Question 17

What is the role of platelets in atherogenesis?

Answer 17

Haemostasis

PDGF stim SMC prolif + migration

Question 18

What is the role of SMC in atherogenesis?

Answer 18

Take up LDL –> Foam Cells

Collagen synth

Question 19

What is the role of MAC in atherogenesis?

Answer 19

Oxidise LDL
Take up LDL –> Foam Cells
Stim SMC prolif + migration

Question 20

What causes atherogenesis?

Answer 20

Endothelial injury (too much LDL / toxins / hypertension)

Question 21

What does endothelial injury cause in atherogenesis?

Answer 21

1. Platelet adhesion / PDGF release –> SMC prolif + migration
2. LDL oxidation + uptake by SMC + MAC
3. Monocyte migration –> intima
4. Local Thrombosis

Question 22

What do Foam Cells secrete and what does that cause?

Answer 22

Cytokines
Causes further SMC stim
Inflamm cell recruitment

Question 23

What are the risk factors of atherosclerosis?

Answer 23

Smoking
Alcohol
Hypertension
Familial Hyperlipidaemia
Obesity

Question 24

How can you prevent atherosclerosis?

Answer 24

Stop smoking
Exercise
Treat hypertension
Aspirin
Statins