Pathological Thrombosis

Question 1

When does pathological thrombosis take plcae?

Answer 1

Occurs in absence of cut or traumatic injury

Question 2

What are the three main causes of thrombosis.

Answer 2

Changes in the intimal surface of a vessel
Changes in the pattern of blood flow
Changes in the blood constituents

Virchows Triad

Question 3

What are the main arteries in the heart?

Answer 3

Coronary arteries

Question 4

Which one of Varchow’s traid describes the alteration in the properties of blood?

Answer 4

Changes in constituents

Question 5

What is atheroma?

Answer 5

A disease of coronary arteries which results in a build up of lipid under the intimal surface

Only occurs in arteries.

Question 6

What can atheroma result in?

Answer 6

Abnormal blood flow- both slow and turbulent flow.

Question 7

What can rupture through the intimal surface of an artery?

Answer 7

Lipids and collagen

Question 8

What happens when platelets and fibri are exposed to abnromal substances like collagen and lipids?

Answer 8

turbulent flow and are deposited as a thrombus

Question 9

What does the thrombum block?

Answer 9

the lumen of the coronary artery

Question 10

Where can the clot form when the thrombum blocks the lumen of the coronary artery.

Answer 10

Clot can now form in the stagnant blood behind the thrombus

Question 11

Give an example for each of Virchow’s Triad.

Answer 11

Changes in the intimal surface of a vessel (for example: atheroma lipid coming onto surface)

Changes in the pattern of blood flow (for example: a bulge of atheroma changing the flow of blood)

Changes in the blood constituents (for example: smoking making it more likely that platelets aggregate)

Question 12

If all three of virchow’s triad occured, what may happen?

Answer 12

Cornoery artery thrombosis

Question 13

What is th conseuqnece of a thrombus bocking the artery?

Answer 13

Complete obstructtuion so no flow beyond blockage

Question 14

What does partial obstruction lead to?

Answer 14

Decreased flow beyond the blockage

Question 15

Define ischaemia

Answer 15

Poor blood flow

Question 16

If ischaemia is sever enoug, what can you get?

Answer 16

Hypoxia

Question 17

Is ischaemic heart tissue painful?

Answer 17

Often

Question 18

What happens to a tissue if the artery supplying it is partially blocked?

Answer 18

rECIEVES LESS BLOOD FLOW (ISCHAEMIA.

Question 19

What happns when there is a severe or total blockage of blood flow?

Answer 19

In severe or total blockage of blood flow the lack of blood flow (ischaemia) leads to severe lack of oxygen (hypoxia) and a localised area of tissue dies

Question 20

What is the localised area of dead tissue called?

Answer 20

Infarct

Question 21

What is the process of tissue dying called?

Answer 21

Necrosis.

Question 22

What is an infarct?

Answer 22

Necrosis as a result of ischaemia (= ischaemic necrosis)

Question 23

Infarcts can occur in other tissues supplied by other arteries: For instance:

Answer 23

Coronary artery thrombosis – infarct in heart
Cerebral artery thrombosis – infarct in brain
Mesenteric artery thrombosis – infarct in gut

Question 24

Define embolism.

Answer 24

A mass of material moving in the vascular system and able to become lodged in a vessel and block its lumen

Question 25

Where do emboli dervive from?

Answer 25

Most emboli are derived from thrombi or clots
They break off and go elsewhere in the circulation

Question 26

What is it called when thrombi or clots embolise?

Answer 26

Thromboembolism

Question 27

Give a common example of thromboembolism

Answer 27

Pulmonary embolism.

Question 28

how does pulmonary embolism occur?

Answer 28

Sluggish flow in leg veins leads to thrombosis and clot formation.

This is because part of thrombus (and clot) breaks off and travels up vein

Question 29

Describe the movement of the embolus to the heart.

Answer 29

Embolus passes into inferior vena cava, then right heart, then pulmonary trunk, and lodges in pulmonary artery branch

Embolous blcos pulmonary artery and get pulmonary infarct.

Question 30

Describe a marrow embolism

Answer 30

Fracture a leg  marrow enters ruptured vein marrow embolises to lung vessels = Marrow embolism

Question 31

Discuess an example of an air embolism.

Answer 31

Knife wound to neck. Air enters vein  air embolises to heart = Air embolism (never inject a person with air in a syringe!)