ICL 3.7: Pathology of Atherosclerosis Flashcards
what are the 3 components of normal arteries?
- endothelial cells
- smooth muscle cells
- extracellular matrixes = elastin, collagen, glycosoaminoglycans
what are the 3 concentric laters of arteries?
- intima
single layer of endothelial cells, minimal subendothelial connective tissue
- media
smooth muscles (concentric layers), external elastic lamina, vasa vasorum
- adventitia
nerve fibers, vaso vasorum
what is the vascular wall’s response to injury?
intimal thickening!
trying to protect itself from further injury
what are some of the major risk factors for atherosclerosis?
- age
- male gender
- family history
- genetic abnormalities
how does gender effect atherosclerosis?
premenopausal, men are more likely
post-menopausal the women are at higher risk because they lose estrogen
in their 70s and 80s it’s the same risk
how does genetics effect atherosclerosis?
- diabets
- HTN
- familial hyperlipidemia
which hyperlipidemia are familial?
type 2 and 3
which factors can we control to limit atherosclerosis?
- HTN
- hyperlipidemia
- smoking
- DM
- CRP**
BUT 20% of cardiovascular events occur without HTN, smoking, hyperlipidemia or DM so what does that leave? CRP!! It’s a devil
what is hypercholesterolemia?
high serum cholesterol
high LDL delivers choleric to peripheral tissues!
HDL mobilizes cholesterol from the tissue and trsports it to the liver to be secreted in the bile
what is CRP?
it’s an acute phase reactant synthesized in the liver and is downstream of a number of inflammatory triggers
it plays a role in inflammation and inflammation is present in all stages of atherosclerosis
assessment of systemic inflammation has become an important factor in risk stratification
CRP is a great marker of inflammation and has become the most simple and most sensitive to assess the risk of ischemic heart disease
how does CRP play a role in the innate immune response?
- opsonizes bacteria
2. activates complement
what happens when CRP is secreted from cells within the intima?
- activates local endothelial cells –> inflammatory cascade starts and then when the leucocytes (specifically monocytes) they start to produce cytokines which again enhance the inflammatory cascade
- induces a prothrombotic state ):
- increases the adhesiveness of the endothelium to leucocytes
what does high sensitivity CRP predict the risk of?
- MI
- stroke
- sudden cardiac death
high sensitivity CRP is the same as CRP but it’s our technological ability to detect minute amounts of CRP – so even tiny amouts of CRP means they’re at a higher risk for these adverse effects!
what is hyperhomocystinemia?
elevated homocysteine
familial hyperhomocystinemia is associated with premature cardiovascular disease in teens and 20s
what can cause hyperhomocystinemia?
- low folate
2. low B12