Vascular pathology

Question 1

What is an atheroma?

Answer 1

Condition characterised by focal accumulation of lipid in the intima of arteries (inner most layer)

Question 2

What is atherosclerosis?

Answer 2

Atheroma causing hardening of arteries

Question 3

List 7 risk factors of atherosclerosis?

Answer 3

Increasing age
Male
Smoking - carbon monoxide damages endothelial cells lining the arteries
Hypertension - blood cells don’t normally contact the endothelium, in hypertension = turbulence - blood cells contact endothelium
Diabetes mellitus
Raised LDL - cholesterol blood levels
Family history

Question 4

List 3 pre-disposing factors of atherosclerosis?

Answer 4

Obesity
Lack of exercise
Low socio-economic status

Question 5

List the stages of an atherosclerosis lesion

Answer 5

Fatty streak
Fibrolipid plaque
Complicated lesion

Question 6

How do veins and arteries differ histologically?

Answer 6

Arteries are smaller and have much thicker walls

Question 7

Describe the wall of an artery?

Answer 7

Inner = internal elastic lamina
Tunica Media
External elastic lamina
Outer = Tunica adventitia

Question 8

Name 2 types of arteries?

Answer 8

Elastic and muscular

Question 9

In a muscular artery what is the tunica media made of?

Answer 9

Smooth muscle cells

Question 10

In an elastic artery where is elastic material found?

Answer 10

Between inner and outer elastic lamina

Question 11

What is the first stage in the formation of an atherosclerosis lesion?

Answer 11

Fatty streak

Question 12

What is the first event occurring during the formation of a fatty streak? What is the effect of this?

Answer 12

Endothelial image leading to permeability, monocyte adhesion to the endothelium so monocytes and LDL can enter the artery

Question 13

What is the major characteristic of a fatty streak?

Answer 13

Foamy macrophages - Monocytes that have entered and injected LDLs. They cannot digest the fat so they sit in the intima

Question 14

Through what process do monocytes enter the intima?

Answer 14

Diapedesis

Question 15

What triggers monocytes to invest LDLs?

Answer 15

Cytokines released form T cells within the fatty streak cause maturation into macrophages, these ingest the LDLs and form foam cells

Question 16

How can a fatty streak develop into a fibrolipid plaque?

Answer 16

T cells release cytokines that cause the release of smooth muscle cells from the tunica media into the intima. These ingest LDLs

Question 17

How does the artery change when a fatty streak develops into a fibrolipid plaque?

Answer 17

The plaque becomes more prominent and elevated

Question 18

How does the artery change when a fatty streak develops into a fibrolipid plaque?

Answer 18

The plaque becomes more prominent and elevated

Question 19

Fibrolipid plaques bulge into what structure?

Answer 19

Lumen of artery

Question 20

Describe what occurs in the fibrolipid plaque?

Answer 20

Smooth muscle cells migrate to the surface of the intima, these are followed by fibroblasts .
Proliferation occurs, there is more lipid uptake and collagen is produced

Question 21

What cells are seen in a fibrolipid plaque?

Answer 21

Foamy macrophages, Smooth muscle cells, lymphocytes and fibroblasts

Question 22

How does a lipid lake form in a fibrolipid plaque?

Answer 22

Foamy macrophages breakdown and form a lipid lake

Question 23

In the fibrolipid plaque stage, is the endothelium intact?

Answer 23

Yes but it is bulging into the lumen - this gives the opportunity for blood cells and platelets to impact on the surface of the fibrolipid plaque

Question 24

What follows the impaction of platelets onto the surface fo the fibrolipid plaque?

Answer 24

Formation of complicated lesion

Question 25

What is the consequence of a complicated lesion forming?

Answer 25

Leads to thrombosis

Question 26

Describe how a complicated lesion forms?

Answer 26

Occlusion of platelets on the surface of the fibrolipid plaque and endothelium layer is lost. Causes the clotting cascade to begin. This forms a thrombus on the plaque.

Question 27

What 5 things occur after the formation of a complicated lesion? Why?

Answer 27

``` Haemorrhage into plaques Plaque fissuring and rupture Embolism Calcification Aneurysm formation Because complicated lesions can occlude the whole artery ```

Question 28

Where does atherosclerosis occur in the arteries?

Answer 28

Bifurcations of arteries | more possibility for platelets to impact

Question 29

Which artery are clinical effects most prominent?

Answer 29

Coronary arteries

Question 30

List some consequences of atherosclerosis?

Answer 30

Ischaemic heart disease Aortic aneurysm Small bowel ischaemia and infarction Peripheral vascular disease

Question 31

What is angina pectorals?

Answer 31

Pain in the left side down the arm during exercise

Question 32

What is myocardial infarction?

Answer 32

Heart muscle dies as a result of ischaemia

Question 33

What is intermittent claudication? What causes it?

Answer 33

Pain in legs during exercise due to peripheral vascular disease

Question 34

Name 3 ways atherosclerosis can be managed?

Answer 34

Lifestyle Medical Surgical

Question 35

How can lifestyle be used to manage atherosclerosis?

Answer 35

Healthy eating, exercise and not-smoking

Question 36

Name 3 drugs used to manage atherosclerosis?

Answer 36

Cholesterol medications, anti-platelet medications, beta blocker medication

Question 37

Name 4 surgical process used to manage atherosclerosis?

Answer 37

Angioplasty Stent Bypass Endarterectomy

Question 38

What is a thrombus?

Answer 38

Solid mass of blood constitutents formed within the vascular system during life

Question 39

How do thrombus and clot differ?

Answer 39

Clot forms outside vascular system

Question 40

What is an embolism?

Answer 40

Passive transport of a substance within the vascular system

Question 41

What is ischaemia?

Answer 41

Inappropriate reduction in blood supply to an organ or tissue

Question 42

What is infarction?

Answer 42

Death of tissue due to ischaemia

Question 43

What is an aneurysm?

Answer 43

Localised permanent abnormal dilation of a blood vessel due to weakening of the blood vessel wall

Question 44

What 3 things are known to result in thrombosis?

Answer 44

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

Question 45

What are Virchows Triad?

Answer 45

Changes in the intimal surface of vessel Changes in the pattern of blood flow Changes in the blood constituents 3 factors that result in thrombosis

Question 46

What is a good example of changes to the intimal surface that will result in thrombosis?

Answer 46

Atherosclerosis - intimal surface ulcerated

Question 47

What is a good example of changes in pattern of blood flow that will result in thrombosis?

Answer 47

Venostasis Blood is stagnant, platelets drop out and clot Injury or compression where the turbulence results in adherence of platelets to endothelium = thrombus

Question 48

What is a good example of changes in the blood constituents that will result in thrombosis?

Answer 48

Anything that makes the blood hyper-coagulable

Question 49

Why do atheromas lead to thrombosis?

Answer 49

Platelets land on top of the atheroma and aggregate and release clotting factors and fibrin forms trapping RBC = more aggregation, causing propagation of the thrombus

Question 50

How do Venus thrombus occurs?

Answer 50

Due to stasis often around valves

Question 51

In what patients often does Venus thrombus occur?

Answer 51

Burns and trauma, after surgery, cardiac failure, pregnancy, immobility, long haul lights

Question 52

What is thrombophlebitis?

Answer 52

Inflammation of the deep vein

Question 53

What is phlebothrombosis?

Answer 53

Stagnation of the deep vein so platelets drop out of circulation and form a thrombus

Question 54

Where in the heart can cardiac thrombosis occur?

Answer 54

Atria or valves

Question 55

In the atrium, conditions like atrial fibrillation and mitral stenosis occurs, how can this cause thrombosis?

Answer 55

Change in blood flow - platelets contact normal endothelium due to turbulence

Question 56

In the valves, thrombosis can occur due to rheumatic fever and endocarditis, why is this?

Answer 56

Due to vegetations, thrombosis occurs on top of these

Question 57

How can thrombosis occur in the ventricle?

Answer 57

If myocardial infarction occurs and the heart wall dies and thrombus can occur here

Question 58

4 fates of thrombi?

Answer 58

Lysis and resolution Retraction and re-canalisation organisation and scarring embolism

Question 59

What is the best outcome of thrombi?

Answer 59

Lysis and resolution

Question 60

Describe lysis and resolution of thrombi?

Answer 60

Complete dissolution of thrombus and complete return to normal tissue architecture

Question 61

Describe retraction and re-canalisation?

Answer 61

Thrombus and clots can both shrink - allowing space within the vessel, blood can move past

Question 62

Describe organisation and scarring?

Answer 62

Organised by fibroblasts causing scarring and reducing blood flow

Question 63

Describe embolism?

Answer 63

Thrombus breaks off and moves passively through the circulation

Question 64

What are the majority of emboli?

Answer 64

Fragments of thrombus

Question 65

Other than fragments of thrombi what can embolism be made of?

Answer 65

Atheromatous debris, vegetations on heart valves, fat, tumours

Question 66

Where do pulmonary embolisms occur?

Answer 66

Venous side - legs (deep vein thrombosis) and pelvic veins

Question 67

How does the size of the embolus effect consequences of pulmonary embolisms?

Answer 67

``` Big = could block pulmonary artery = sudden death Small = smaller arteries = chest pain breathlessness, hypertension ```

Question 68

Why does systemic embolism occur?

Answer 68

Thrombosis in left side of heart or aterial system

Question 69

What do the consequences of systemic embolism depend on?

Answer 69

Size and site the thrombus lodges

Question 70

What causes infarction?

Answer 70

Atheromas, thrombosis, embolism, vasculitis, compression, spasm, hyperviscosity

Question 71

What determines infarction?

Answer 71

Vascular anatomy Duration of occlusion (length of time the thrombus is there) Metabolic requirements of tissue - brain has high requirements for glucose and oxygen - few minutes = death) general circulatory factors - reduction in nutrients due tot heart failure Reperfusion

Question 72

What can cause aneurysms?

Answer 72

Atherosclerosis | Mycotic - infection