Hyperlipidaemia Flashcards
what are the stages of atherothrombosis
1 - normal 2 - fatty streak 3 - fibrous plaque 4 - atherosclerotic plaque 5 - plaque rupture/fissure & thrombosis
at what stage is there angina/TIA/PAD
Fibrous plaque
Atherosclerotic plaque
what is the pathogenesis of atherosclerotic plaques
1 - endothelial damage 2 - protective response results in production of cellular adhesion molecules 3 - monocytes + T lymphocytes attach 4 - migrate through wall 5 - lipid rich foam cells 6 - fatty streak and plaque
what are the big 4 of CV risk factors
Hypertension
Hypercholesterolemia
Smoking
Diabetes/obesity
what are the little 4 of CV risk factors
Physical inactivity
Alcohol
Stress
Biological factors
what are the types of lipoproteins
Chylomicrons Very low-density lipoproteins Intermediate-density lipoproteins Low density lipoprotein High density lipoprotein
what lipoprotein is strongly associated with atherosclerosis and CHD events
LDL cholesterol
what does a raised triglycerides make you susceptible to
increased risk of CHD
increased pancreatitis risk
which cholesterol has a protective quality and what is it’s relationship with CHD
HDL
lower HDL, higher risk for CHD
what is the relationship between triglycerides and HDL cholesterol
HDL tends to be low when Triglycerides is high
what lowers HDL
smoking, obesity, physical inactivity
what is the exogenous metabolic pathway concerned with
the transport and utilisation of dietary fat
what happens in the GI tract
Dietary fat is broken down into cholesterol, fatty acids and mono- and di-glycerides.
Together with bile acid they carry lipid to absorptive sites in the duodenum
what happens after absorption in the duodenum
chylomicrons are formed which enter the blood stream to be transported to the liver
what hydrolyse the chylomicrons once in enters the plasma and what does it do
lipoprotein lipase
releases the triglyceride core, free fatty acids and mono- and diglycerides for energy production or storage
what happens to the residual chylomicron
further dilipidation resulting in the formation of chylomicron remnants
what happens to the chylomicron remnants
taken up by the liver and undergo lysosomal degradation
are either used for cell membrane synthesis or excreted as bile salts
how much of the triglyceride is absorbed
virtually all
what does VLDL do
transports triglycerides from the liver to the rest of the body
what enzymes causes VDLD to undergo delipidation
lipoprotein lipase
what happens to VLDL
transformed into LDL
the larger VLDL particles are lipolysed to IDL
what enzyme reacts with smaller VLDL and IDL particles
hepatic lipase
what is the product of the endogenous pathway and what happens to it
LDL
absorbed by macrophages within the arterial wall to form lipid-rich foam cells
what is the mechanism of action of statins
inhibits HMG-CoA reductase - the enzyme involved in the rate-limiting step in the formation of cholesterol
what do statins do
reduce total cholesterol and LDL cholesterol
increase NO availability
what are clinical markers for dyslipidaemia
Xanthelasma Tendon xanthomas Tuberous xanthomas Eruptive xanthomas Striate palmar xanthomas
what are xanthelasma
xanthomas of eyelids
may or may not be associated with hyperlipidemia
what are tendon xanthomas
infiltration of tendon by lipid
what are tuberous xanthomas
lipid deposits in the dermis and subcutis
what are tuberous xanthomas indicators of
familial or acquired hypertriglyceridemias
biliary cirrhosis
what is eruptive xanthomas
small reddish-yellow papules
seen on buttocks, posterior thighs, body folds
what happens in association with eruptive xanthomas
abrupt increase in serum triglyceride levels
what are the two types of hypertension
essential - no underlying cause
secondary - underlying cause
what does smoking do
Increases blood pressure
Decreases HDL
Damages arteries and blood cells
Increases risk of heart attacks
how does type 2 diabetes mellitus lead to atherosclerosis
increased LDL, VLDL
Decreased HDL
increased oxidative stress-endothelial dysfunction-vascular damage-smooth muscle cell proliferation
increased platelet adhesiveness-hypercoagulation
