Atheroma and Thrombosis Flashcards Preview

EMS - Mechanisms Of Disease > Atheroma and Thrombosis > Flashcards

Flashcards in Atheroma and Thrombosis Deck (27):
1

What is the word used to describe "degeneration of arterial walls characterised by fibrosis, lipid deposition and inflammation which limits blood circulation and predisposes to thrombosis"

Atherosclerosis

2

The following vessels are commonly affected by ....
-bifurcations
-abdominal aorta
-popliteal arteries
-carotid vessels
-circle of willis

Atherosclerosis

3

What are the risk factors of atherosclerois?

1) Age
2) Male
3) Family history
4) Genetic

5) Cholesterol
6) Hypertension
7) smoking
8) Diabetes

4

What is the first step of atherosclerosis?

Endothelial inhjury

5

In hyperlipidaemia where does lipid accumulate in the vessel?

-Inner most part of the vessel - the intima

6

Foam cells

Monocytes will migrate to the intima due to endothelial injury, Ingest the lipid and become foam cells

7

What is the fatty streak stage of atherosclerosis?

1) accumulation of lipids in intima
2) formation of foam cells

8

What secretes chemokines to attract monocytes, lymphocytes and smooth muscle cells?

foam cells

9

What secretes connective tissue?

Smooth muscle cells proliferate and secrete connective tissue

10

What forms atherosclerotic plaque?

Fat, extracellular material, leukocytes and smooth muscle forms atherosclerotic plaque

11

Describe the structure of an atheromatous plaque?

1) fibrous cap
2) Necrotic centre
3) media

12

What is the difference between a clot and thrombus?

CLOT:
-stagnant blood
-enzyme process
-elastic
-adopts shape of vessel

THROMBUS:
-Dependent on platelets
- firm

13

How do platelets becomes activated?

Platelets bind to collagen exposed by endothelial damage and become activated.

14

What do platelets secrete?

Alpha Granules:
1)fibrinogen
2) fibronectin
3) PDGF

Dense granules:
-chemotactic chemicals

15

What is Virchow's Triad?

Changes in the following lead to thrombus formation and platelet adhesion:
1) Intimal surface of vessel
2) partten of blood flow
3) Blood constituents

16

Describe how Virchow's Triad is present in arterial thrombus formation?

1) Plaque rupture changes the intimal surface of the vessels and causes turbulent flow.
2) Hyperlipidaemia - changes blood constituents.
3) Platelets bins and fibrin is produced entrapping RBC

17

Desrcribe how Virchow's Triad is present in Venous Thrombus formation?

1) Intimal change : valves
2) Change in blood flow : slows due to immobility
3) change in blood constituents:
-inflammatory mediators (infection)
-factor V leiden (hypercoaguable state)
-Oestrogen

18

What are thrombi in the heart known as?

Mural thrombi

19

What are mural thrombi?

Thrombi in the heart which occur over areas of endomyocardial injury. e.g. MI, myocarditis, arrhythmias and cardiomyopathy

20

What is an embolus?

a mass of material in the vascular system that is able to lodge and block the vessel

21

What are the risk factors for a venous thromboembolism (VTE) ?

Acquires:
-immobility
-maligancy
-previous VTE
-heart failure
-Oestrogens
-obesity
-pregnancy
-renal disease
-smokers

Genetic:
Thrombotic disorders e.g.
-Factor V Leifden
-Protein S deficiency

22

What are the clinical effects of a small, medium and large pulmonary embolism?

Small = if multiple can cause pulmonary hypertension

Medium = acute respiratory / cardiac failure

Large = Death

23

Where does a systemic emboli arise?

1) Heart (during MI or Atrial Fib)
2) arterial circulation (atheroma)

24

Where do infective emboli arise?

1) Vegetations on infected heart valves

25

What type of emboli can lead to a mycotic aneurysm?

Infective embolism

26

What are the different types of embolism?

-pulmonary
-venous thromboembolism
-systemic
-infective
-Gas
-amniotic
-fat
-foreign body

27

What type of embolism leads to a granulomatous reaction?

foreign body embolism