B.1 Dyslipidaemia 2

Question 1

What is dyslipidaemia ?

Answer 1

The abnormal level of cholesterol and other lipids, also called fats, in the blood

Question 2

What is hypercholesterolaemia?

Answer 2

Elevated plasma cholesterol which leads to atherosclerosis

Question 3

What is atherosclerosis?

Answer 3

Focal lesions (plaques) on the inner surface of an artery (hardening)

Question 4

What does atherosclerosis lead to ?

Answer 4

Ischaemic heart disease (IHD): Inadequate blood flow to the heart.

Peripheral vascular disease(PVD): Leg arteries become narrow, pain upon exercise

Cerebrovascular disease: Pre disposal towards stroke

Question 5

What are the risk factors of atherosclerosis?

Answer 5

Genetics 
Hypercholesterolemia 
Hypertension
Smoking 
Obesity
Hyperglycaemia 
Reduced physical activity
Infections

Question 6

What drugs could induce dyslipidemia?

Answer 6

Beta-blockers
Thiazides 
Corticosteroids 
Retinoids
Oral contraceptives
Anti-HIV drugs

Question 7

What are HDL, LDL, VLDL?

Answer 7

High-density lipoproteins (good )
Low-density lipoproteins (bad)
very-low-density lipoproteins (bad)

Question 8

What is the role of chylomicrons?

Answer 8

Transports triglycerides and cholesterol from the GI tract to the liver. Free FA released and cholesterol is stored, oxidized to bile salts, or released to LDL, VDL, HDL

Question 9

What is the role of VLDL?

Answer 9

Transports cholesterol and TGs to the tissues, where the TGs are removed leaving large components of cholesterol.

Question 10

What is the role of LDL?

Answer 10

Large components of cholesterol, taken up by the liver and tissues, via endocytosis via an LDL receptor

Question 11

What is the role of HDL?

Answer 11

Absorbs cholesterol from cell breakdown and transfers it into VLDL and LDL (liver for excretion)

Question 12

What is Xanthomata?

Answer 12

A sign by which people with hypercholesterolaemia/ dyslipidaemia experience:

Yellow streaks
Yellow plaque, on eyes and wrists

This can indicate to a doctor to examine patients cholesterol levels

Question 13

Describe the process of atherogenesis

Answer 13

Atherogenesis: inflammatory response to injury

1. Smoking, hypertension, and turbulent flow can all cause damage to the vascular endothelium
2. Damage causes migration of monocytes/macrophages to the site. This causes inflamation.
3. Reaction oxygen species (superoxide and hydrogen peroxide are released and cause oxidative damage.
4. The LDL becomes oxidises (oxLDL), making the binding of LDL to its receptor damaging to the receptor.
5. The damage of the receptor prevents the correct uptake of LDL, therefore more LDL will reside between the endothelium and arterial wall.
6. This results in the formation of foam cells which are cholesterol-rich (fatty streaks), which can cause further problems in the future

Question 14

What happens when plaque starts to narrow the arteries?

Answer 14

Narrowing to >70% results in angina
This impairs blood flow to the muscles
Causing pain upon exercise

Question 15

What happens when plaque becomes unstable/ ruptures?

Answer 15

Platelets stick to the surface (clot) and block the artery.

This leads to a heart attack in coronary circulation or stroke in the brain

Question 16

How would atherogenesis be managed?

Answer 16

Stop smoking 
Treat HT
Treat diabetes melitus 
Change andy drug-induced medication
Have a low cholesterol diet (small effect as most cholesterol in the body is made by the liver)