Pathology Flashcards
What can the underlying problems be in secondary hypertension?
Renal disease Endocrine disease Aortic disease Renal artery stenosis Drug therapy - corticosteroids
What is usually the underlying disease of ab MI?
Atheroma
Is a fatty streak reversible?
Yes
What comes after a fatty streak formation (if not resolved)?
Fibrofatty plaque
What is smooth muscle replaced by in a fibrofatty plaque?
Dense fibrous tissue - non elastic
What is arterial stenosis?
Narrowing of the arterial lumen
What does an arterial thrombosis give rise to?
Infarction
What happens in arterial dissection?
Split within the media causing a false lumen to form and blood flows within the walls
Where does a clot form?
Outside the vessel
Where does thrombosis occur?
Within the vessel
Virchow’s Triad
Endothelial injury
Hypercoaguability
Turbulent blood flow
What 2 things are needed for a thrombus to form?
Platelet activation and fibrin production
What 2 things do collagen bind to on a platelet?
Glycoprotein Ia/IIb and von Willebrands factor
What do platelets release to attract more platelets?
vWF
Platelet activating factor
Thromboxane A2
ADP
Define atherosclerosis?
Formation of plaques at the site of endothelial injury
Why doesn’t thrombosis occur in the arteries?
The flow is high so the platelets don’t get enough time to all clump up
Causes of endothelial Injury
Hypertension Toxins Smoking Infection Autoimmune disorders - vasculitis
Where does blood flow slow down?
Deep veins
What does protein C and S do?
Degrade factor V and VIII
What does antithrombin III do?
Degrades factor II, IX and X
What is plasmin?
A clot buster
Define Embolism
A dislodged thrombus which travels round the body until it gets stuck somewhere
Causes of an embolism?
Thrombosis Air Septic Fat Amniotic Tumour
Define ischaemia
Insufficient blood supply
Define infarction
Cell death as a result of inadequate tissue perfusion (ischaemia)
