5.3 Heart Disease

Question 1

What is an atheroma?

Answer 1

A fatty deposit that forms within the wall of an artery.

Question 2

How does an atheroma begin?

Answer 2

As fatty streaks that are accumulations of white blood cells that have taken up Low-Density Lipoproteins

Question 3

What is atheromatous plaque made up of?

Answer 3

• Cholesterol
• Fibres
• Dead muscle cells.

Question 4

Where does atheromatous plaque most regularly occur?

Answer 4

In larger arteries

Question 5

How do they cause the flow of blood to narrow?

Answer 5

They bulge into the lumen of the artery

Question 6

What two conditions do atheromas increase the risk of?

Answer 6

• Thrombosis
• Aneurysm

Question 7

What is a thrombus?

Answer 7

A blood clot

Question 8

What is the condition called when you have a thrombus?

Answer 8

Thrombosis

Question 9

What happens when the wall of an artery is weakened from an atheroma?

Answer 9

The weakened points swell to form a balloon-like, blood-filled structure, called an aneurysm.

Question 10

What happens when an aneurysm bursts?

Answer 10

Haemorrhaging and loss of blood to the region of the body served by that artery.

Question 11

What is a myocardial infarction?

Answer 11

A reduced supply of oxygen to the muscle of the heart.

Question 12

What are the four main risk factors of getting CHD?

Answer 12

• Smoking
• High Blood
• Pressure
• Blood Cholesterol
• Diet

Question 13

What is the single most effective way of increasing life expectancy?

Answer 13

Stopping smoking

Question 14

What are the two constituents of tobacco smoke that increase the likelihood of heart disease?

Answer 14

• Carbon Monoxide
• Nicotine

Question 15

How does Carbon Monoxide increase the risk of heart disease?

Answer 15

It combines irreversibly with haemoglobin to form carboxyhaemoglobin.

Question 16

How does the formation of carboxyhaemoglobin affect the body?

Answer 16

Because it reduces the oxygen-carrying capacity of the blood, causing the heart to work harder, leading to raised bloody pressure.

Question 17

How does the intake of nicotine increase the risk of heart disease?

Answer 17

Nicotine stimulates the production of adrenaline, which raises heart rate and pressure.

Question 18

How does nicotine affect red blood cells?

Answer 18

It makes them more sticky & therefore leads to a higher risk of thrombosis and myocardial infarction.

Question 19

What are the 3 reasons high blood pressure increases risk of heart disease?

Answer 19

• The heart is working harder and is therefore more prone to failure.
• Higher blood pressure in the arteries means they are more likely to develop an aneurysm & burst.
• To resist the higher pressure, the walls of the arteries may thicken and harden, restricting blood flow.

Question 20

What are the two types of lipoproteins?

Answer 20

• High-density lipoproteins
• Low-density lipoproteins

Question 21

What type of lipoprotein increases risk of heart disease?

Answer 21

Low-density lipoproteins

Question 22

How do LDLs increase risk of heart disease?

Answer 22

They transport cholesterol from the liver to the tissues, infiltrating artery walls, leading to the development of atheroma and hence heart disease.

Question 23

What two diet-related aspects increase risk of heart disease?

Answer 23

• High levels of salt
• High levels of saturated fat

Question 24

How do high levels of salt increase risk of heart disease?

Answer 24

Raise blood pressure

Question 25

How do high levels of saturated fat increase risk of heart disease?

Answer 25

They increase LDL levels and hence blood cholesterol concentration.