Atherosclerosis Flashcards
What is atherosclerosis
Hardening of the arteries and narrowing due to plaque
What is the difference between a normal artery and atherosclerosis artery
Normal artery blood flows to the cardiac muscle but in an atherosclerosis artery there is plaque meaning blood flow is blocked
How is severity of atherosclerosis determined?
Severity is determined by how narrow the artery. The more narrow it is the more likely hood of it forming a thrombus
What is the pathogenesis of atherosclerosis (plaque formation)
- There is an injury and LDL deposits in the tunica intima and becomes oxidised
- This activates endothelial cells
- And monocytes then bind to receptors and move into the tunica intima
- When they enter they become macrophages
- Macrophages then bind with the oxidised ldl and become foam cells
- These foam cells promote the smooth muscle to move from the tunica media into the intima
- This causes collagen synthesis
- Too much of this causes the foam cells to rupture and the contents can form a thrombus and impede blood flow
What do vldl do?
Transport cholesterol and triglycerides towards adipose tissues
Lipoprotein lipase then removes the triglycerides turning it into ldl
What do ldl do?
Binds to ldl receptors and is taken into the cell by endocytosis
What are the risk of high levels of vldl and ldl
Increased risk of CAD and atherosclerosis
What are hdl
They bind to the surface of cells and pump out excess cholesterol
They also transport cholesterol away from tissues.
High levels are good
Why can cholesterol levels remain high after medication and diet
- It takes a while to see results as cholesterol can remain in the bloodstream for a while
- Non adherence
Why are fibrates and statins not used together
Fibrates increase the risk of myopathy when combined with a statin
Why is simvastatin taken at night
Most cholesterol is made at night and the enzyme that inhibits the cholesterol works better at night
Should atorvastin be taken at night
No but needs to be taken the same time everyday
What is the moa of statins?
Inhibit synthesis of cholesterol in liver through inhibition of HMG coa reductase
IN BNF
What are the guidelines for lipid levels
Cholesterol = 5mmol/L
LDL= 3mmol/L or lower
HDL = more than 1
How does omega 3 help
They decrease plasma levels of triglycerides
They inhibit platelet function
Reduce inflammation
