week 6- CV risk testing Flashcards
• what are some tests for determining risk of CAD?
o Lipid Panel: direct (Total cholesterol, HDL, TGs), Calculated (LDL, VLDL, Ttl Chol/HDL ratio)
o Lp(a): Lipoprotein (a)
o Lipoprotein electrophoresis
o Hcy: Homocysteine
o hs-CRP: Highly-sensitive C-Reactive Protein
o Fibrinogen
• What are some tests for determining cardiac damage?
o CK: Total Creatine Kinase o CK-MB: Isoenzyme of CK, myocardial-bound o cTnT: Cardiac TroponinT o cTnI: Cardiac Troponin I o AST o LDH o Myoglobin
• Facts on heart dz?
o Leading cause of death (M and F), 600,000 americans per year (1/4 deaths) = each minute
o Coronary heart dz MC (385,000 deaths)
o MI every 34 secs in US
o US $108.9 billion each year
• Compare rates of CA and CVD deaths by age:
o CA slightly higher in 40s-70s
o >75 CVD rates get much higher
• Rank the US regions with highest heart dz death rates?
o South//Midwest
o NE coast
o SW (CA and NV)
• What is the Framingham risk calculator?
o Estimate 10-yr risk of MI o For 20+, don’t have CVD or DM o Age and gender o Meds for HTN? o total cholesterol, HDL, smoker, systolic BP
• what is a lipid panel/lipoprotein profile?
o Measures blood cholesterol
o Direct: total chol, HDL, TGs
o Calculatd: LDL, VLDL, ttl chol/HDL ratio
• What are blood lipids?
o water-insoluble, extractable by nonpolar (fat) solvents (alcohol, ether)
o = fatty acids, neutral fats, waxes, steroids
o Compound lipids: glycolipids, lipoproteins, phospholipids
o Main groups: cholesterol/esters, glycerol esters (TG), FAs, PLs
• How do lipids move thru body?
o intestinal mucosa →chylomicrons → liver o Chylo (huge) release TGs and some cholesterol to muscle and adapocytes → remnants taken up by liver o VLDL, IDL, LDL, formed in liver, carries fat and cholesterol to body’s cells. o HDL (tiny) carry fat and cholesterol back to liver for excretion
• What happens when oxidized LDL gets high
o →atheroma in walls of arteries → atherosclerosis (foam cells, smooth mm, necrotic core, LDL; bw intima and endothelium)
o HDL can remove cholesterol from atheroma
o Atherogenic cholesterol = LDL, VLDL, IDL
• What is cholesterol?
o A sterol, → bile acids, steroid hormones, cell membranes
o Mostly endogenous, made in liver
o Diet influences blood levels 10-20%
o 30-60% in diet absorbed → mixed w conjugated bile acids, PLs, FAs, MGs
• What are normal and critical cholesterol levels?
o Adult: 400, look at genetic markers
• What are relative % of cholesterol constituents?
o 60-70% LDL
o 25-35% HDL
o Rest is VLDL, chylomicrons
o Day-to-day values can vary by as much as 15%, 8% in 1 day
• What can interfere w total chol measurement?
o Seasonal: higher in fall & winter than in spring & summer
o Estrogens: ↓ plasma LDL; PG ↑ all Cholesterols
o Position: Standing higher than sitting; sitting higher than recumbent by 15%
• When are ↑ total cholesterol levels seen?
o Type II familial hypercholesterolemia: faulty LDL uptake recpetors, tx resistant
o Hyperlipoproteinemia Types II and III, st IV & V
o Cholestasis; Hepatocellular dz & Biliary cirrhosis
o Nephrotic syndrome; Chronic renal failure
o Pancreatic neoplasms; Hypothyroidism (LDL); DM
o High cholesterol diet; Obesity
• When are ↓ total cholesterol levels seen?
o Severe liver dz o Myeloproliferative dzs o Hyperthyroidism o Diet: malabsorption, malnutrition, Vegan o Certain chronic anemias o Inflammation o Acute illness o COPD o Tangier Dz o 30-50% drop from baseline 1 week after acute MI
• What are triglycerides?
o Most abundant dietary fat; 95% of all fat stored in adipose
o Prime function: energy for cell
o hydrolyzed into FAs, glycerol, MGs in intestines w lipase and bile acids
o →absorption → reconstituted into chylo-microns
o Unlike cholesterol, diet greatly affects levels
• What are normal and critical TG levels?
o Desirable: < 150 mg/dl o Borderline High: 150 – 199 o High: 200 – 499 o Very High: > 500 o Must fast; if >400, need Lp electrophoresis to directly measure LDL
• What can cause increased TG levels?
o Hyperlipoproteinemia Types I, IIb, III, IV, V o Liver disease, Alcoholism o Nephrotic syndrome/ renal disease o Hypothyroidism, DM, Pancreatitis o Glycogen storage diseases o MI, Gout, High fat diet
• What can cause dereased TG levels?
o Severe illness o Malnutrition o Malabsorption o Hyperthyroidism o Hyperparathyroidism o COPD
• What can interfere w TG measurement?
o ↑: Transient after food or alcohol, prego, OCPs, acute illness colds flu, smoking, physical inactivity/obesity, drugs
o ↓: Transient decrease after exercise, drugs
• What are lipoproteins?
o Lipid-protein complexes in which lipids (hydrophobic) are transported in blood
o spherical hydrophobic core of TG or cholesterol esters surrounded by amphophilic mono-layer of PLs, cholesterol, apolipoproteins
• what are the 2 types of lipoprotein metabolism?
o Exogenous: dietary fat → chylomicrons → glycerol, FFAs, MGs
o Endogenous: chylomicron remnant → liver → VLDL, IDL, LDL, HDL
• What are chylomicrons?
o Large particles made by intestines, ↑ diet TG (90%), ↓chol, PL, ↓ protein (1%)
o Less dense than water, ↑ lipid:protein ratio, floats
o Cause of “milky” plasma
o lipoprotein lipase → ↓TG = REMNANT.
