Unit 2 KA7 - pathology of cardiovascular diseases

Question 1

what is atherosclerosis?

Answer 1

the accumulation of fatty material forming an atheroma or plaque beneath the endothelium
the atheroma grows and so the artery thickens and loses its elasticity
the diameter of the lumen becomes reduced and blood flow becomes restricted

Question 2

what does fatty material consist of?

Answer 2

cholesterol, fibrous material and calcium

Question 3

what does atherosclerosis result in?

Answer 3

increased blood pressure

Question 4

what is the root cause of various cardiovascular diseases? (name them)

Answer 4

atherosclerosis

angina, myocardial infarction, stroke, peripheral vascular disease

Question 5

what is thrombosis?

Answer 5

blood clotting as a protective device to prevent loss of blood at a wound
an atheroma may rupture, damaging the endothelium
the presence of the damaged cells leads to the release of blood clotting factors that result in a cascade of reactions
this results in the conversion of the enzyme prothrombin (which is always in blood but inactive) into its active form thrombin
thrombin then catalyses the change of a soluble plasma protein fibrinogen into insoluble threads of fibrin
the fibrin threads form a meshwork that clots the blood, seals the wound and provides a scaffold for the formation of scar tissue

Question 6

what is a thrombus?

Answer 6

formation of a blood clot

Question 7

thrombosis in a …….. artery may lead to a ……. ………..

Answer 7

coronary, myocardial infarction

Question 8

how is an embolus formed?

Answer 8

in some cases a thrombus may break lose forming an embolus which travels through the bloodstream until it blocks a blood vessel

Question 9

a thrombosis in a coronary artery can lead to a heart attack because…

Answer 9

the embolus formed can block the blood supply to the heart muscles

Question 10

what may lead to a stroke?

Answer 10

aa thrombus that causes a blockage in an artery to the brain

Question 11

what happens to the tissues during both a stroke and heart attack?

Answer 11

the cells are deprived of oxygen so this leads to the death of the tissues

Question 12

name three peripheral vascular disorders

Answer 12

pulmonary embolism, peripheral vascular disease, deep vein thrombosis

Question 13

what are peripheral arteries?

Answer 13

arteries other than the aorta, coronary artery and carotid artery

Question 14

what is peripheral vascular disease?

Answer 14

the narrowing of the arteries (other than those of the heart and brain) due to atherosclerosis
mostly affects leg arteries
blood flow to the legs is restricted and pain is felt due to the lack of oxygen

Question 15

what is deep vein thrombosis?

Answer 15

the formation of a thrombus (blood clot) in a deep vein

causes the area to be painful, swell up and veins close to the skin surface can become engorged with blood

Question 16

what is a pulmonary embolism?

Answer 16

when an embolus blocks a pulmonary artery

the person experiences chest pains, breathing difficulties and palpitations

Question 17

what is cholesterol?

Answer 17

a type of lipid found in the cell membrane

Question 18

why is cholesterol important?

Answer 18

needed for the synthesis of sex hormones - testosterone, progesterone and oestrogen

Question 19

where is cholesterol produced?

Answer 19

by all cells, however, 25% of the total production takes place in the liver

Question 20

what causes an increase in cholesterol levels in the blood?

Answer 20

a diet high in saturated fats or cholesterol

Question 21

the body produces …… types of ……… that transport ……….. around the body

Answer 21

2, lipoproteins, cholesterol

Question 22

transports cholesterol to ……
most cells have LDL ……… that take LDL into the cell where the cholesterol is released for ………. in the cell
once a cell has sufficient ……….. a……….. ……….. system……… the synthesis of new …….. …………….
the LDL then circulates in the…….. where it may deposit…………. in the …………. forming ……………..

Answer 22

body cells, receptors, use, cholesterol, negative feedback, inhibits, LDL receptors, blood, cholesterol, arteries, atheromas

Question 23

what is the role of HDL?

Answer 23

HDL transports excess cholesterol from the body cells to the liver for elimination
this prevents the accumulation of cholesterol in the blood

Question 24

what is a healthy HDL to LDL ratio? why?

Answer 24

HDL removes excess cholesterol so having a higher ratio of HDL to LDL will result in lower blood cholesterol and a reduced chance of atherosclerosis

Question 25

how can the HDL to LDL ratio be improved?

Answer 25

taking part in regular physical activity to raise HDL levels
changes in the diet to aim to reduce levels of total fat and top replace saturated fats with unsaturated fats

Question 26

what are statins?

Answer 26

drugs prescribed by a doctor to lower blood cholesterol levels by inhibiting the synthesis of cholesterol by liver cells