Week 206 - Myocardial Infarction

Question 1

What type of inheritance pattern does Familial Hyperlipidaemia have?

Answer 1

Autosomal Dominant

Question 2

List 3 clinical signs of hyperlipidaemia.

Answer 2

1) Xanthelasma
2) Tendon xanthomata
3) Corneal arcus

Question 3

What is considered the ideal total cholesterol blood level?

Answer 3

<5mmol/L

Question 4

What is considered to be a very high cholesterol level?

Answer 4

> 7.8mmol/L

Question 5

Which chromosome holds the gene responsible for Familial Hypercholesterolaemia?

Answer 5

Chromosome 19

Question 6

What is the main aim of non-drug treatment for hypercholesterolaemia?

Answer 6

Maintaining a lean body weight

Question 7

What lifestyle changes should be encouraged to manage hyperlipidaemia?

Answer 7

Reduce – fat intake, alcohol consumption
Smoking cessation
Avoid thiazides, oestrogens and non-selective B-blockers
Increase exercise

Question 8

What is the most potent pharmacological treatment for hypercholesterolaemia?

Answer 8

Statins

Question 9

In which groups of patients should you be particularly careful when prescribing statins?

Answer 9

 Children
 Women of reproductive age
cholesterol is source of steroid hormones so reducing cholesterol could also reduce steroid hormone production

Question 10

When should statins be taken and why?

Answer 10

In the evening > cholesterol synthesis is most active at night

Question 11

What is the reasonably common alternative pharmacological treatment for hypercholesterolaemia/hyperlipidaemia?

Answer 11

Fibrates

Question 12

What do fibrates (fibric acid derivatives) do?

Answer 12

Reduce blood triglyceride levels by:
-Decreasing VLDL production in liver (therefore reducing triglyceride carrier potential)
-Modestly increase HDL levels
Have NO effect of LDL levels

Question 13

What is the function of a lipoprotein?

Answer 13

To carry/transport lipids in the blood

Question 14

Describe the process of atherosclerotic plaque formation.

Answer 14

Damage/insult on the endothelial lining which releases factors such as ADP and *** causing platelets and macrophages to adhese and aggregate. Lipids, calcium and cellular debris accumulate too and smooth muscle cells begin to form a fibrous cap over the plaque > plaque is now unable to disperse.

Question 15

What do macrophages become within an atherosclerotic plaque?

Answer 15

Foam cells

Question 16

How does Aspirin work as an antithrombotic drug?

Answer 16

It irreversibly inhibits platelet cyclo-oxygenase-1 (COX-1) through acetylation. COX-1 catalyses thromboxane and prostaglandin production > reduces thromboxane A2 and prostaglandin

Question 17

What is prostacyclin (PG12)?

Answer 17

A vasodilator and platelet inhibitor produced by platelets and vascular endothelium.

Question 18

What clinical sign is virtually diagnostic of heterozygous familial hypercholesterolaemia?

Answer 18

Tendon Xanthomata > occurs in ~70% of all affected individuals

Question 19

What two major clinical signs occur around the eyes of many individuals with familial hypercholesterolaemia?

Answer 19

Xanthelasma and corneal arcus (premature)

Question 20

What are yellow, fatty plaque lesions associated with hyperlipidaemia that occur on the body in areas besides the eyes?

Answer 20

Xanthomas (xanthelasma is the most common form of xanthoma)

Question 21

Why is chromosome 19 associated with Familial hypercholesterolaemia?

Answer 21

Because the LDL receptor is coded for on chromosome 19 and it is dysfunction of any of the 5 steps involved in LDL receptor function that can result in the condition

Question 22

How is familial hypercholesterolaemia best managed?

Answer 22

With a statin. High dose atorvastatin has been proven to reverese intimal thickening that occurs in FH

Question 23

How do statins work in the treatment of hypercholesterolaemia?

Answer 23

They inhibit HMG CoA in the liver – the rate limiting step in cholesterol synthesis. Increase the removal of LDL and IDL( by inc. their receptors), decrease the production of LDL and VLDL. Slightly increase HDL

Question 24

Why are fibrates contraindicated in gallstone disease?

Answer 24

They themselves can cause gallstone formation by increasing cholesterol excretion via bile

Question 25

Why should fibrates be used with caution in renal impairment?

Answer 25

May increase creatinine levels

Question 26

List the main contraindications of fibrates.

Answer 26

Severe hepatic impairment, hypoalbuminaemia, primary biliary cirrhosis, gallstone disease, nephrotic syndrome, pregnancy and breast-feeding