Atherosclerosis thrombosis and embolism Flashcards
we will cover atherosclerosis thrombosis and emboli types of risk factors development treatment prevention ischaemia and infarction shock
how many people die each year from a hospital acquired venousthrombo embolism
32000
describe the physiology of blood vessels and endothelial cells
inner layer: intima
middle media
outer- adventitia
what is the difference between the media in a vein and an artery
the media in the artery is much bigger diameter
what is the origin of endothelial cells
mesodermal origin
what are endothelial cells found
interior surface of blood vessels and the lymphatics and on the inside of the heart( called the endocardium)
what are endothelial cells called inside the heart
endocardium
what is the function of the endothelial cells
semi selective barrier function- allows WBC to move out to the area of infection (diapedesis)
- angiogenesis
- mediator of coagulation
- blood pressure control
- fluid filtration
what happens with prolonged inflammation to the endothelial cells
increased permeability and tissue swelling
what clotting factors do endothelial cells mediate
von willibrands factor- stabilises factor VIII which binds to collagen linking platelets
heparan sulphate- inactivates clotting cascade
what does heparan sulphate control
inactivates clotting cascade
which diseases is endothelial cell dysfunction
many diseases
septic shock
hypertension
behcets
how else can endothelial cell dysfunction arise
tobacco and air pollution
trans fat consumption
how can endothelial cell dysfunction improve
smoking cessation
weight loss
improved diet
exercise
what is a atheroma
is an accumulation of intracellular and extracellular lipid in the intima of large and medium sized arteries
what is atherosclerosis
the thickening and hardening of arterial walls as a consequence of atheroma
why do atheromas form
due to chronic endothelial cell damage- in the arteries as BP is higher
how does an atheroma develop 11 steps
- chronic endothelial cell dysfuction
2 endothelial dysfunction
3 entrance of LDL in intimia
4 lipid engulfed by macrophages
5 flat yellow(fatty streak) early atheroma
6 accumulation of lipids- in macrophages and smooth muscle wall
7 raised yellow lipid plaque
8 extracellular lipid deposits and collagen deposition and calcification
9 fibrous cap over the lipid core(fibroatheroma)
10 ulceration of plaque
11 predisposition to thrombus formation- advanced complicated plaque
what are the risk factors for atheroma
high LDL/low HDL hypertension diabetes sedentary lifestyle obesity smoking
what are the two forms of prevention for the formation of atherosclerosis
primary- risk factor modification
secondary- includes regulation medications such as aspirin and the prevention of the recurrence of events
when do early atheromas start forming
in your early 20s-30s
progressive
which medications can be used to stabilise the plaques and prevent rupture
statins
what medication can be used if the atheroma was to rupture
antithrombotic agents
which sites can be affected
aorta-
coronary artery
iliac and popliteal arteries
internal carotid arteries
iwhat happens if the aorta is affected by atheroma
weakening of the aorta can cause aortic aneurysm and then risk of rupturing
what happens if the coronary artery is affected by atheroma
narrowing of the artery lumen-reduced blood flow and ischaemia
thrombus formation over plaque-occlusion of the lumen causing MI
what happens if the iliac and popliteal arteries are affected by atheroma
narrowing of the artery lumen
reduced blood flow leading to ischaemia
what happens if the internal carotid arteries are affected by atheroma
emboli travels p the the brain causing ischaemia (if transient) or infraction( TIA/stroke)
what is a thrombus
a structured solid mass or plug of blood constituents formed within the heart or blood vessels during life
what is thrombosis
the process of thrombus formation-