Pathology- Thrombosis, Embolism, Infarction Flashcards

1
Q

what is ischaemia?

A

insufficient blood supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is infarction?

A

death of tissue as a result of ischaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is thrombosis

A

the formation of a blood clot inside a blood vessel, obstructing the flow of blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is embolism

A

the blockage of an artery by an embolus (foreign body e.g. blood clot (mass of coagulant), air bubble etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is atheroma also known as

A

atherosclerosis, hardening of the arteries, coronary heart disease, ischaemic heart disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

atheroma is the principle cause of death and disability in the western world true or false

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the aetiology of atheroma

A

smoking, hypertension, hyperlipidemia, diabetes, age (older), sex (males), genetics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what causes primary endothelial injury

A

smoking, hypertension, hyperlipidemia, immune factors, toxins, viruses, turbulent blood flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does increased LDL and reduced HDL - or - increased V-CAM, IL-1 or TNF expression lead to

A

accumulation of lipids and macrophages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what causes the migration of smooth muscle cells

A

PDGF (platelet derived growth factor), FGF (fibroblast growth factor), TGF beta (transforming growth factor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are foam cells

A

dead macrophages containing consumed LDL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what surrounds the fatty streak

A

fibrous cap (collagen fibres) and damaged endothelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what happens to atheromatous plaques over time

A

progress and become complicated

fatty streak- fibrofatty plaque- complicated plaque (with overlying thrombus)

further loss of luminal potency and arterial wall weakness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

under what circumstances (3) is atheromatous narrowing of an artery likely to produce critical disease

A

it is the only artery supply a tissue/organ

small artery diameter

overall blood flow is reduced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the complications of atheroma

A

stenosis, thrombosis, aneurysm, dissection, embolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is stenosis and what does it lead to

A

narrowing of the arterial lumen,

reduced elasticity,

reduced flow in systole,

tissue ischaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the clinical effects of cardiac ischaemia

A

reduced exercise tolerance

angina

unstable angina

myocardial infarction

cardiac failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

describe cardiac fibrosis and what it causes

A

loss of cardiac myocytes- replacement by fibrous tissue

loss of contractility, reduced elasticity and filling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

can arterial stenosis affect any artery

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what can arterial stenosis in carotid arteries cause

A

TIA, stroke and vascular dementia (reduction in cognitive skills due to reduction in blood flow to brain)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what can arterial stenosis cause when in the renal arteries

A

hypertension and renal failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what can arterial stenosis cause when in the peripheral arteries

A

claudication (cramping in lower leg due to insufficient blood supply) and foot/leg ischaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what does superadded

A

to add in a way that compounds the effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what are the clinical effects of thrombosis

A
infarctions; 
myocardial 
cerebral 
renal 
intestinal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what is an aneurysm
Abnormal and persistent dilatation of an artery due to a weakness in its wall
26
what are the types of aneurysm
``` mycotic (fungus) atherosclerotic dissecting congenital arteriovenous traumatic syphillitic ```
27
where is the most common site for an aneurysm
abdominal aorta
28
what are the complications of an aneurysm
rupture, thrombosis, embolism, pressure erosion of adjacent structures, infection
29
what is an arterial dissection
splitting within the media by flowing blood
30
what are the risk factors for arterial dissection
middle age +/- atheroma
31
what is a false lumen
filling of blood inbetween tunica intima and media
32
what can artial dissection cause
sudden collapse, high mortality
33
what conditions are associated with aortic dissection
atheroma, hypertension, trauma, coarctation, marfan's, pregnancy
34
what are the usual consequences caused by embolis
cerebral infarct renal infarct and renal failure lower limb infarction
35
describe the structure of athero-embolism
cholesterol clefts within embolic material
36
where sites are preferred for thrombosis formation
VIRCHOWS TRIAS sited of endothelial injury turbulent blood flow hypercoaguable blood
37
how is a thrombus formed
intravascular coagulation which requires; - platelet activation - fibrin production via coagulation cascade
38
is the formation of t thrombus an active or passive process
active
39
what is the difference between activated and inactivation platelets
activated platelets (more sticky) attract and aggregate with other platelets. also aggregate with fibrin
40
what is the start and end point of the coagulation cascade
start platelets end fibrin
41
what happens to collagen when the endothelium is lost
exposed and binds to glycoprotein Ia/IIb and von Willebrands factor (vWF) (surface receptors) on platelets activating them
42
what event during platelet activation allows them to bind
increase in intergrins (transmembrane receptors that facilitate cell-extracellular matrix (ECM) adhesion)
43
what binds fibrinogen on platelets
glycoprotein IIb/IIIa
44
what do activated platelets release
granules to attract other platelets (vWF, platelet activating factors (PAF), thromboxane A2 (TXA2), ADP
45
why is it called the coagulation cascade
One factor activates another and so on like a domino effect
46
what does the domino affect of the coagulation cascade allow
Sequences provide lots of opportunities for checks and balances – areas to inhibit or stimulate
47
what is the common pathway both the intrinsic and extrinsic pathways of the coagulation pathways
converting fibrinogen to fibrin to cross linked fibren
48
what is the coagulation cascade dependant on
calcium dependant
49
what initiates the extrinsic coagulation pathway
tissue injury
50
what does the intrinsic pathway start with
hageman factor (FXII) and kalikrien
51
what is Prothrombin Time (PT)
blood test measuring how long it takes blood to clot (intrinsic pathway)
52
what joins together yo make the common pathway of the extrinsic coagulation pathway
tissue factor (TF) binds with factor VII
53
what is the blood test used to characterise blood coagulation in the extrinsic pathway
Activated Partial Thromboplastin Time (APTT)
54
what factors activate fibrinogen and turn it into fibrin
II and XIII
55
what is required to make factors II, VII, IX and X
vitamin K
56
what is vitamin K
fat soluble vitamin, stored in the liver
57
what factors are missing in liver disease
II, VII, IX and X
58
what does warfarin stop the production of
factors II, VII, IX and X
59
describe hypercoagulable blood
extra thick
60
in a normal arterial system why is there not coagulation
as high flow system so pro-coagulant materials washed along before being able to do anything
61
what is needed for thrombosis to occur in arterial systems
underlying atherosclerosis
62
what is atherosclerosis
formation of plaques etc. at sites of endothelial damage
63
why is there increased endothelial damage at branched arteries
as turbulent flow where arteries branch
64
what are common resulting conditions of atherosclerosis
cerebral infarction, carotid atheroma-emboli (TIA or cerebral infarcts), myocardial infarction (cardiac failure), aortic aneurysm, peripheral vascular disease, gangreen
65
what are complications of atherosclerosis
thrombosis, exercised induced angina, stable angina, plaque rupture
66
what is unstable angina
when coronary arteries have been occluded due to thrombus
67
what is primary vasculitis
autoimmune disease characterised by inflammation directed at vessel walls (immune system attacks own vessels)
68
name 4 branching arteries
coronary arteries, above bifurcation of aorta, origin and division of carotid arteries, renal arteries, superior mesenteric artery
69
why do branching vessels pose such a risk- give 2 examples
as vessels distal to branches are susceptible to embolism and infarction stroke, small bowel infarction
70
what does turbulence cause
endothelial cell injury stasis
71
what is margination
increased contact of platelets etc with vessel walls
72
what is stasis
when blood flow slows down
73
where does blood flow slow down (stasis)
deep venous system, faulty valves, venous insufficiency
74
what causes hypercoaguability
dehydration, polycythemia (number of cells), leukaemias (increase white blood cells)
75
what degrades clots
plasmin
76
what are three anti clotting proteins
protein C, protein S and antithrombin III
77
what factors do proteins C and S degrade
factor V and VIII
78
what factors do antithrombin III degrade
II, IX and X
79
what is factor V leiden
a variant (mutated form) of human factor V which causes an increase in blood clotting (hypercoagulability) (inherited disorder)
80
what other deficiencies can lead to hypercoaguability
protein C deficiency, protein S deficiency, antithrombin III deficiency
81
what are components involved in anti thrombotic mechanisms
plasmin, protein C and S, antithrombin III also heparin
82
what is heparin
anticoagulant drug
83
what are secondary causes of hypercoagulability
``` Prolonged immobility Significant tissue injury – burns, RTA Antiphospholipid syndrome – autoimmune Myocardial infarction Atrial fibrillation (irregular cardiac rhythm) cancer therapt marantic endocarditis ```
84
how does cancer cause hypercoagulability
Activate coagulation cascade through tumour produced TF, mucin, inflammatory cytokines
85
how does therapy cause hypercoagulability
many chemotherapeutic agents injure endothelium and increase risk of thrombosis
86
what are more low risk secondary causes of hypercoagulability
the pill, smoking, renal disease, cardiomyopathy
87
what is an embolism
Dislodge thrombus – travels around the vascular system until it gets stuck
88
what can cause an embolism (the thrombus)
clot, air, septic, amniotic fluid, tumour, fat
89
how do cells die from hypoxia
lack of ATP, increase calcium,leads to breakdown of membranes, cytoskeleton and DNA plus releases pro death factors