Atheroma

Question 1

What is an atheroma?

Answer 1

Accumulation of intra and Extracellular lipid in the tunica media of large and medium sized arteries.

Question 2

What is atherosclerosis?

Answer 2

Thickening and hardening of the walls of arteries as a result of atheroma.

Question 3

What is a simple plaque?

Answer 3

This is a raised yellow or white area which has an irregular outline. It is widely distributed.

Question 4

What properties does a complicated plaque possess?

Answer 4

There is haemorrhage into the plaque, calcification and aneurysm formation.

Question 5

What are the most common sites for atheroma formation?

Answer 5

Aorta, coronary artery, carotid artery, cerebral artery and leg arteries.

Question 6

What microscopic changes are seen early in atheroma formation?

Answer 6

There is proliferation of smooth muscle cells, accumulation of foam cells and Extracellular lipid.

Question 7

Name three microscopic changes which occur later in atheroma formation.

Answer 7

Fibrosis, necrosis and Cholestrol clefts.

Question 8

What is plaque fissuring?

Answer 8

This is when material within the plaque moves.

Question 9

What problem can atheroma cause to the heart?

Answer 9

Ischaemic heart disease.

Question 10

What can be seen on a post mortem of heart tissue which indicates ischaemic heart disease?

Answer 10

There will be areas of white fibrotic tissue.

Question 11

Name three things that cerebral ischaemia can lead to

Answer 11

Transient ischaemia attack, cerebral infarction and multi-infarct dementia.

Question 12

What can mesenteric infarction cause?

Answer 12

Malabsorption, ischaemic collitis and intestinal infarction.

Question 13

What is peripheral vascular disease?

Answer 13

This is when there is problem with the blood supply to the legs.

Question 14

What is intermittent claudication?

Answer 14

This is when there is pain in the legs and it gets worse on exercise, causing the person to have to stop.

Question 15

State risk factors of atheroma.

Answer 15

Age, gender, hyperlipidaemia, smoking, alcohol, diabetes, infection, lack of exercise, hypertension, obesity, stress

Question 16

What is the thrombogenic theory for atheroma formation?

Answer 16

This suggest that repeated thrombi formation in the smooth muscle tissue is where the lipid is derived from.

Question 17

What is insudation theory of atheroma formation?

Answer 17

When there is endothelial injury, this causes inflammation and increased permeability of the membrane to lipid.

Question 18

What is the reaction to injury hypothesis for atheroma formation?

Answer 18

This proposes that oxidised LDL causes the initial damage. This injury increases permeability and platelet adhesion occurs. Smooth muscle cells proliferate and migrate.

Question 19

What is the monoclonal hypothesis for atheroma formation?

Answer 19

This proposes that each plaque is monoclonal and displays abnormal growth control.

Question 20

Name the cell types involved in atheroma formation.

Answer 20

Endothelial cells, platelets, smooth muscle cells, neutrophils, lymphocytes and macrophages.

Question 21

How do the smooth muscle cells change during atheroma formation?

Answer 21

They take up lipid and become foam cells.

Question 22

How do macrophages contribute to atheroma formation?

Answer 22

They take up LDL and become foam cells, and then secrete proteases which cause modification to the matrix and stimulate smooth muscle cell proliferation.

Question 23

Name four causes of endothelial injury.

Answer 23

Raised LDL, hypertension, toxins and haemodynamic stress.

Question 24

What happens after endothelial injury in atheroma formation?

Answer 24

Platelet adhesion and smooth muscle cell proliferation and migration. This is followed by insudation of lipid and then uptake into the smooth muscle cells and macrophages.

Question 25

What preventative strategies can be employed for atheroma formation?

Answer 25

No smoking, treat hypertension, reduce fat and alcohol intake, take regular exercise and control weight.

Question 26

What interventions are employed with atheroma formation?

Answer 26

Modify diet, stop smoking, treat diabetes, lower lipids and treat hypertension.