Atherosclerosis Flashcards
What types of vessels develop atherosclerosis
Arteries
the only times veins do is when they are sed for bypass
What causes atherosclerosis
Endothelial damage due to metabolic derangements (DM) or physical force (BP), with deposits of platelets and lipoproteins (LDL) under the endothelium
What do LDL under the endothelium attract
Macrophages
What do platelets release
They release growth factors, which stimulate proliferation of smooth muscle cells in artery wall
This causes cholesterol and LDL accumulation in macrophages
What are foam cells
Macrophages filled with LDL’s
How are cholesterol crystals formed
lipid laden smooth muscle cells die and release lipid into interstitial spaces to be deposited as cholesterol crystals
What role do macrophages have after they phagocytize pieces of damaged smooth muscle cells
secrete cytokines and TNF, which stimulate collagen production (BAD, damage/hardening)
What leads to sclerosis (hardening)
the repair of initial arterial lesions with collagen depositions
What is an atheroma
a lesion that bulges into the lumen of the artery
It splits the tunica media
What is atherosclerosis related to
AGE!
What is the consistency of an atheroma
center is soft (lipid and cellular debris)
Outer covering is a fibrous surface cap (collagen and smooth muscle)
Can an atheroma be reversed
yes.
until secondary calcification, then it can’t be reversed
What is a major complication of an atheroma
local tissue degeneration causing hardening of the vessel (calcification)
Why are atheroma visible on XR
lipids released from dead cells attract calcium salts (radio dense)
What are RF for atherosclerosis
Age Sex (male>female until menopause when they are equal) Heredity (familial predisposition) Lipid metabolism (lipid accumulation in atheroma) Hypertension Obesity (HLD) Diabetes Cigarette smoking Stress (constant)
What can menopausal women do to reduce progression of atherosclerosis
Take replacement estrogen therapy
What can modify the genetic predisposition to atherosclerosis
Healthy lifestyle and balanced diet
What is familial hyperchoesterolemia
defect of LDL receptors not allowing lipoproteins into the liver
best known cause for familial atherosclerosis
How does hypertension affect atherosclerosis development
elevated pressure of blood compresses intimal cells causing ischemia and cytokine release
Cytokine promotes proliferation of smooth muscle cells
-HTN also damages platelets causing aggregation
What is diabetic microangiopathy
damage caused to small blood vessels due to hyperglycemia
Who is aortic atherosclerosis most common in
older men
People over 50 with some degree of atherosclerosis
-Mildest forms found in young/middle aged pts with fatty streaks
Whitman eventually happen to fatty streaks
they form atheromas (lipid rich bulging lesions)
What happens when an atheroma ruptures
They become calcified, reducing elasticity of the vessel
Is blood pressure affected by atherosclerosis
an atherosclerotic aorta is rigid and can’t adapt to changing blood pressures of a normal cardiac cycle
This leads to HTN in the vessel
