Thromboembolic Disease

Question 1

Name thromboembolic disorders

Answer 1

Ischaemic stroke
Myocardial infarction
Pulmonary embolus
Ruptured abdominal aortic aneurysm

Question 2

What is the the definition of a thrombus

Answer 2

A solid mass present within the vascular system during life formed by the constituents of blood

Question 3

If a blood clot forms after death is that a thrombus

Answer 3

No because a thrombus forms during life

Question 4

What is the difference in consistency between a thrombus and post mortem clot

Answer 4

Thrombus: firm and brittle

Post mortem clot: gelatinous

Question 5

What is the differnce in colour between a thrombus and post mortem clot

Answer 5

Thrombus: pale or red with lines of zahn

Post mortem clot: pale on top and dark red underneath

Question 6

What is the difference in adherence to the vessel wall between a thrombus and post mortem clot

Answer 6

Thrombus: adherent to the vessel wall

Post mortem clot: non adherent

Question 7

What are lines of zahn

Answer 7

Pale and dark areas that form lines within the thrombus

Question 8

What are the 2 appearances of thrombi

Answer 8

Pale thrombi

Red thrombi

Question 9

Where does pale thrombi tend to form

Answer 9

High flow enviroment e.g heart and arteries

Question 10

Why are pale thrombi pale in colour

Answer 10

Composed of mainly platelets

Question 11

Where do red thrombi tend to form

Answer 11

In veins where there is low flow of blood

Question 12

Why are red thrombi red in apperance

Answer 12

They are composed of trapped red blood cells

Question 13

Name examples of pale thrombi

Answer 13

Arterial thrombi

Cardiac thrombosis

Question 14

What are arterial thrombi

Answer 14

Pale thrombi that form in the arterial

Question 15

What are the causes of arterial thrombi

Answer 15

Atherosclerosis
Aneurysms
Inflamamtion, vasculitis

Question 16

What are the appeances of arterial thrombi

Answer 16

Mural thrombosis

Occlusive thrombosis

Question 17

What is a mural thrombosis

Answer 17

A thrombus that affects a lare vessel so its adherent to one side fo the vessel wall

Question 18

What is an occlusive thrombosis

Answer 18

Thrombi that occurs in medium/small vessels completely blocks the vessel

Question 19

In the heart where can cardiac thrombosis cocur

Answer 19

Atria
Valves
Ventricles

Question 20

What can thrombosis in the atria be associated with

Answer 20

Atrial fibrillation

Question 21

What can thrombi in the valves be associated with

Answer 21

Rheumatic feber
Infective endocarditis
Non bacterial thrombotic endocarditis

Question 22

What can thrombi in the ventricles be associated with

Answer 22

Myocardial infarction

Question 23

Name an example of red thrombi

Answer 23

Venous thrombosis

Question 24

What factors increase the risk of venous thrombosis

Answer 24

Immobility 
Post operative 
Trauma
Myocardial infarction 
Cognitive heart failure 
Thrombophlebitis 

I.e anything that causes the low flow of blood through the veins

Question 25

Describe how a thrombus forms

Answer 25

1. Haemostasis begins when there is a damage to the endothelium 2. Blood vessels vasoconstrict 3. Primary haemostatic plug forms that is composed of platelets over the damaged endothelium 4. Secondary haemostasis occurs where fibin is deposited among the platelets to form a fibrin mesh worl 5. Mature thrombus forms

Question 26

What is the virchows triad

Answer 26

3 factors that promote thrombosis

Question 27

What are the 3 factors within the virchows triad

Answer 27

1. Endothelial injury: can be by inflammation or hyper cholesterol 2. Abnormal blood flow: this can be due to the clot that slows the blood flow or stasis e.g af, bed rest 3. Hypercoagulability: can be exacerabated by inherited or acquired conditions

Question 28

When a thrombus forms what are the 2 things that can happen to it

Answer 28

1. Resolve the thrombus | 2. Become progressed i.e become fibrotic by replacing RBC/platelets by fibrosis tissue

Question 29

What is an embolism

Answer 29

A mass (embolus) within the blood stream and impaction to a distant side from its poitn of origin

Question 30

What is an emboli composed of

Answer 30

Thrombi | Fat,air, tumour etc

Question 31

How does pulmonary embolism occur

Answer 31

1. Fragmentation of venous thrombus 2. Thrombotic embolis is carried through the larger veins to the right side of the heart 3. From the heart embolus is taken to the pulmonary arteries (smaller arteries) where it lodges

Question 32

What is a systemic embolism and how does it occur

Answer 32

1. Fragmentation of the left side of the heart or aorta 2. Thrombotic embolus is carried through smaller arteries 3. Embolus lodges in a branch of the aorta where the diameter is smaller than the embolus diameter

Question 33

What is ischaemia

Answer 33

Cell injury caused by reduced blood flow to a tissue or reduced venous drainage

Question 34

How does ischaemia occur

Answer 34

1. Thrombus forms in a vessel 2. This reduces the oxygen flow to the tissue 3. Atp produced by mitochondria reduces 4. Cell swelling and clumping of nuclear chromatin occurs

Question 35

What are the causes of ischaemia

Answer 35

Occlusion by a thombus or embolus Intrinsic disease of cells External compresion

Question 36

What is a infarction

Answer 36

Ischaemic necrosis caused by occlusion of either the arterial supply or the venous drainge of a tissue/organ

Question 37

What are the 2 types of infarcts

Answer 37

White infarcts | Red infarct

Question 38

What is a white infarct and the mechanism

Answer 38

A white colour infarct due to lack of blood, occurs in the arterial occlusion of solid organs with the end arterial circulation

Question 39

What is a red infarct and the mechanism

Answer 39

Red coloured infarct due to accumulation of blood ``` Mechanism: Loss spongy tissue Venous occlusion Dual circualtion Previous congestion ```

Question 40

Is infarction a reversible or irreverible

Answer 40

Irreversible

Question 41

Is ichaemia reversible or irreversible

Answer 41

Reversible