Atherosclerosis Flashcards
(26 cards)
Factors involved in plaque development
Endothelial dysfunction
Smooth muscle cell proliferation
LDL trapping
Inflammatory cell recruitment
Foam cell formation
Necrotic core formation
Where do plaques mainly develop
Places of disturbed blood flow
Bifurcation
What do endothelial cells do?
Control size of artery
Control transport of molecules across artery
What causes activation of endothelial cells?
Turbulent flow patterns
What is consequence of activated endothelial cells?
More leaky
Allow more LDL through artery wall
Attract immune cells to area
How do endothelial cells respond to disturbed flow?
Increase:
Response to inflammatory stimuli
Reactive O2 species production
Permeability
Apoptosis and senescence
What do smooth muscle cells do?
Produce collagen giving strength to artery
Dilation and constriction
Relationship between endothelium and smooth muscle cell function
Functional endothelium suppresses migration and proliferation of smooth muscle cells
Endothelial dysfunction takes handbrake off
Role of smooth muscle cell in plaque development
Form and maintain fibrous cap- apoptosis leads to the weakening of this
Respond to damage caused by plaque that triggers further proliferation
What is role of LDL in plaque development
LDL trapped in plaque and becomes oxidised
Macrophage function
Immune cells
Phagocytose foreign material or dying cells
Oxidise LDL
Macrophage role in atherosclerosis
Can’t down regulate scavenger receptors
Consume too much LDL and die leaving oxidised LDL in artery wall along with its own cholesterol
Risk factors for atherosclerosis
Age
Smoking
Diet
Inactivity obesity
Diabetes
Hypertension
Genes
Impact of smoking atherosclerosis
Increase toxic chemicals
Increase free radicals and inflammatory cytokines
Poor diet atherosclerosis
Increase LDL
Increase BP
Less antioxidant
Less fibre
Inactivity atherosclerosis
Increase endothelial dysfunction
Increase BP AND LDL
Obesity atherosclerosis
Central adiposity
Increased metabolic syndrome risk
Hypertension atherosclerosis
Endothelial dysfunction
Thickening of artery
LDL trapping
Tortuous blood vessels
What is type 1 MI
Atherothrombosis 70-75% of cases
What percent of MI due to plaque rupture
65% Type 1 MI
Problem with a plaque rupture
Blood communicates with necrotic core precipitating a thrombus
Eroded plaque percent of MI
31% type 1 MI
Problem caused by endothelial erosion
Loss cells overlaying a plaque precipitate a thrombus
