Pathophysiology of atheroma (part 1)

Question 1

What is the other term for atheroma?

Answer 1

atherosclerosis

Question 2

What is atherosclerosis?

Answer 2

formation of focal elevated lesion (plaques) in intima of large and medium sized arteries

Question 3

What is the effect of atheromatous plaques forming in coronary arteries?

Answer 3

ischemia

Question 4

What can angina cause?

Answer 4

myocardial ischemia

Question 5

Is arteriosclerosis atheromatous?

Answer 5

it is not!

Question 6

What is arteriosclerosis?

Answer 6

age-related change in muscular arteries

smooth muscle hypertrophy, apparent reduplication f internal elastic laminae, intimal fibrosis –> decrease vessel diameter

Question 7

What duplicates in arteriosclerosis?

Answer 7

internal elastic laminae

Question 8

What does arteriosclerosis cause in the elderly population?

Answer 8

contributes to high frequency of cardiac cerebral, colonic and renal ischemia in elderly

Question 9

What is the earliest significant lesion of an atheroma called?

Answer 9

fatty streak

Question 10

How does the fatty streak appear as?

Answer 10

yellow linear elevation of intimal lining

Question 11

What comprises the fatty streak?

Answer 11

masses of lipid-laden macrophages

Question 12

What will a fatty streak go on to develop?

Answer 12

atheromatous plaque

Question 13

Who has a fatty streak?

Answer 13

young children

Question 14

Can a fatty streak disappear?

Answer 14

yes

Question 15

After the fatty streak what is next to form?

Answer 15

early atheromatous plaque

Question 16

What is the structure of a fully developed atheromatous plaque?

Answer 16

central lipid core with fibrous tissue cap, covered by arterial endothelium

Question 17

What provides the structural strength in the fully developed atheromatous plaque?

Answer 17

collagen

Question 18

What immune cells are recruited from the arterial endothelium? (reside in the fibrous cap)

Answer 18

inflammatory cell (macrophages, T-lymphocytes, mast cells)

Question 19

What is the central lipid core rich in?

Answer 19

cellular lipids/debris derived from macrophages (died in plaque)

Question 20

Why are the macrophages in the lipid core called foamy?

Answer 20

due to uptake of oxidised lipoproteins via specialised membrane bound scavenger receptor

Question 21

What usually occurs late in plaque development?

Answer 21

dystrophic calcification

Question 22

Where do atheromatous plaques form ?

Answer 22

at arterial branching points/bifurcations (turbulent flow)

Question 23

What additional elements does a complicated atheroma have?

Answer 23

features of established atheromatous plaque (lipid-rich core, fibrous cap) plus…

haemorrhage into plaque (calcification)

plaque rupture/fissuring

thrombosis

Question 24

What does complicated atheroma lead to?

Answer 24

it has clinical consequences

Question 25

What is the most important risk factor for atheroma?

Answer 25

hypercholesterolaemia

Question 26

What type of cholesterol is atheroma risk?

Answer 26

LDL

Lack of membrane receptors for LDL

elevated LDL levels

Question 27

What are signs of major hyperlipidaemia?

Answer 27

primary or acquired

need biochemical evidence: LDL, HDL, total cholesterol, triglycerides

corneal arcus (premature)

tendon xanthomata (knuckles, Achilles)

xanthelasmata

Question 28

What are risk factors for major hyperlipidaemia?

Answer 28

premature, family history MI/atheroma

smoking

hypertension

diabetes mellitus

male

elderly

acceleration of plaque formation driven by lipids