Pathology of Cardiovascular Disease (CVD)

Question 1

What is Atherosclerosis?

Answer 1

The accumulation of fatty material (consisting mainly of cholesterol), fibrous material and calcium, forming an atheroma or plaque.

Question 2

Where does an atheroma form?

Answer 2

Beneath the endothelium of the artery wall.

Question 3

What does an atheroma do?

Answer 3

As an atheroma grows, the artery thickens and loses its elasticity. An atheroma reduces the diameter of the lumen of an artery, which restricts blood flow and results in increased blood pressure.

Question 4

What is Atherosclerosis the root cause of?

Answer 4

Various cardiovascular diseases including angina, heart attack, stroke and peripheral vascular disorders.

Question 5

What happens if an atheroma ruptures?

Answer 5

The damage to the endothelium causes the release of clotting factors. Clotting factors cause the enzyme prothrombin to be converted into its active form thrombin.

Question 6

What does thrombin do?

Answer 6

Causes molecules of the soluble plasma protein fibrinogen to form threads of insoluble fibrin protein.

Question 7

What happens to Fibrin during Thrombosis?

Answer 7

Fibrin threads form a mesh work that platelets adhere to, forming a blood clot which seals a wound and provides a scaffold for the formation of scar tissue.

Question 8

What is thrombosis?

Answer 8

The formation of a blood clot (thrombus) in a vessel.

Question 9

What happens if a thrombus breaks loose?

Answer 9

It forms an embolus that travels through the bloodstream until it blocks a blood vessel.

Question 10

What may happen f thrombosis occurs in a coronary artery?

Answer 10

A myocardial infarction (heart attack).

Question 11

What may happen if thrombosis in an artery in the brain occurs?

Answer 11

A stroke.

Question 12

What does thrombosis normally result in?

Answer 12

The death of some of the tissue served by the blocked artery as the cells are deprived of oxygen.

Question 13

What are peripheral vascular disorders?

Answer 13

Narrowing of arteries due to Atherosclerosis of arteries other than those of the heart and brain.

Question 14

What can blood clots result in?

Answer 14

Deep Vein Thrombosis (DVT) and pulmonary embolism.

Question 15

What is DVT?

Answer 15

The formation of a blood clot in a deep vein, most commonly in the lower part of the leg. In DVT, pain is experienced in the leg muscles due to a limited supply of oxygen.

Question 16

How is a pulmonary embolism caused?

Answer 16

Part of an thrombus breaking free and travelling through the bloodstream to the pulmonary artery where it can cause blockage, resulting in chest pain and breathing difficulties.

Question 17

What is cholesterol?

Answer 17

A component of cell membranes and a precursor for steroid synthesis.

Question 18

How is most cholesterol synthesised?

Answer 18

By the liver from saturated fats in the diet.

Question 19

What do lipoproteins contain?

Answer 19

Lipid and protein.

Question 20

What does High Density Lipoprotein (HDL) do?

Answer 20

Transports excess cholesterol from the body cells to the liver for elimination and so prevents the accumulation of cholesterol in the body.

Question 21

What does Low Density Lipoprotein (LPD) do?

Answer 21

Transports cholesterol to body cells. Most cells have LDL receptors that take LDL into the cell, where it releases cholesterol.

Question 22

What happens once a cell has sufficient cholesterol?

Answer 22

A negative feedback system inhibits the synthesis of new LDL receptors and so LDL circulated in the blood where is may deposit the cholesterol in the arteries, forming atheromas.

Question 23

How is Familial Hypercholesterolaemia (FH) caused?

Answer 23

By an autosomal dominant allele that results in individuals developing high levels of cholesterol.