Atherosclerosis Flashcards
where does atherosclerosis usually occur and why
arteries
high pressure blood can damage artery endothelium
narrow lumen means it can become blocked easily
what is the process of atherosclerosis
damage to endothelium (high pressure)
inflammatory response
white blood cells gather at damaged wall
build up of cholesterol, calcium salts and fibrous tissue (blood clotting cascade) sticks to endothelium
fatty build up causes atheroma and plaque
plaque hardens and artery wall becomes less elastic
self perpetuating (positive feedback) keeps occurring
why is atherosclerosis an example of positive feedback
arteries lumen narrows due to plaque
blood pressure increases
can cause other arteries to become damaged
what happens if an artery becomes fully blocked
lack of oxygen to cells
cells begin to respire anaerobically
lactic acid builds up causing pain
cells die
what are the consequences of atherosclerosis
angina- narrowing of coronary arteries causes chest pains as cardiac muscle lacks oxygen
coronary heart disease- if collagen is exposed clotting cascade happens. Blood supply to heart can become blocked causing heart attacks
stroke- blood supply to brain is cut off (by blood clots) brain cells will be starved of oxygen and could lead to permanent damage or death
aneurysms- if artery is blocked blood can form behind blockage causing a bulge (could burst)
what are the risk factors of atherosclerosis
high blood pressure
high cholesterol
obesity
smoking
