CSIM1.61 CDVS D/z 1

Question 1

Describe the formation of an atheroma

Answer 1

Macrophage foam cell

Lipid accumulation intracellularly: enlargement of foam cell

Pooling of extracellular lipid

Central pool of extracellular lipid

Lipid core with fibrotic layers

Complicated lesion with bleeding

Question 2

What kind of changes occurs in the first half of an atheroma development?

Answer 2

Mainly lipid accumulation

Question 3

What kind of changes come after lipid accumulation stage in an atheroma development

Answer 3

Smooth muscle and collagen

Question 4

Describe a type 5 atheroma lesion

Answer 4

Central lipid pool
Macrophages with lots of lipids
Smooth muscle cell proliferation in intima
Formation of fibrotic cap over lesion

Question 5

Descrive a type 6 atheroma

Answer 5

Complicated lesion
Ulceration and fissure of plaque happens
Revealing plaque contents and bleeding
Blood clots to form a thrombus which can embolise
Wall of vessel becomes weakened with more fibrous tissue taking over.

Question 6

What are the more likely sites of atheroma formation?

Answer 6

All arteries >1mm

Tend to occur at bifurcations and sites of high haemodynamic stress

Question 7

Describe the vascular effects of an atheroma

Answer 7

Narrowing of lumen -> ischaemia -> infarction

Break off = embolus

Embolus can go to other organs like brain -> stroke

Weakened walls + high BP -> aneurysm

Question 8

Organ effects of an atheroma

Heart, brain, legs, gut, kidney

Answer 8

Heart -> myocardial infarct or angina

Brain -> TIA or stroke

Legs -> claudication i.e. Pain in calf on walking, or necrosis/gangrene if severe

Gut -> ischaemia, necrosis, bloody diarrhea

Kidney -> atrophic, kidney failure, RAAS cascade increase, BP increase, risk of heart failure increase

Question 9

Risk factors for atheroma

Answer 9

Age, male, family hx, genetics

Hyperlipidaemia, hypertension, smoking, diabetes, obesity

Question 10

According to the lipid hypothesis of atheroma formation, what types of cholesterol are bad?

Answer 10

LDL is the bad

HDL is good

Vldl and IDL are neutral

Question 11

How does an atheroma form according to the response to injury hypothesis?

Answer 11

Injury to endothelium
Adhesion molecules release
Macrophages adhere to endothelium
LDL follow macrophages infiltration into endothelium
Macrophage engulf lipids -> foam cells
SM + collagen + calcification occurs in later stages