What is the pathophysiologic “event” that causes majority of myocardial infarctions? (p.27-28)
- MI occurs when plaque is unstable, ruptures, and a thrombus forms
- Result is total obstruction of arterial lumen at affected site
- Or, segment of thrombus breaks away, travels to more distal site in coronary microcirculation, and obstructs vessel at that point
- Thrombosis = cause for MI
Why do patients with MI often develop lactic acidosis?
- Poor delivery of oxygen to tissues greatly diminishes oxidative metabolism
- Cells obtain most of their energy by anaerobic process of glycolysis, which leads to tremendous quantities of excess lactic acid in blood
Review complications of heart failure. (p.30)
- Occurs when heart can no longer maintain adequate cardiac output to meet metabolic needs of the body
- Pump failure = myocardium can no longer contract normally, therefore stroke volume decreases
Review lipoprotein transport and metabolism.
Know where various lipoproteins are synthesized and major component (TG, cholesterol, protein) of each lipoprotein. (p.18)
- Lipids and proteins transported in circulation via dynamic particles called lipoproteins.
- Primary function of lipoprotein and transport lipid components in blood
- Exogenous fat transport
- Endogenous fat transport
- Reverse cholesterol transport
What is the role of lipoprotein lipase (LPL) in lipid metabolism?
- Hydrolyzes chylomicron TG and fat stored in adipose tissue and liver cells
- Both adipose tissue and liver can gain large quantity of enzyme lipoprotein lipase
- Hydrolyzes TG of chylomicrons as they come in contact with endothelial wall, releasing FA and glycerol
- Causes hydrolysis of PL
Will insulin influence synthesis of LPL? (p.18)
Insulin plays role in synthesis of LPL
Know where various lipoproteins are synthesized and major component (TG, cholesterol, protein) of each lipoprotein. (p.16)
What types of fatty acids increase blood cholesterol levels? (p.19)
- Saturated fatty acids
- o C12 – Lauric acid
- o C14 – Myristic acid
- o C16 – Palmitic acid
Would these fatty acids have greater or lesser effect on increasing blood cholesterol levels than intake of dietary cholesterol per se?
Synergistic effect on elevating plasma cholesterol levels
What lifestyle recommendations would you suggest to reduce risk of heart disease and why?
- Decrease LDL-C <200 mg/dL
- Increase HDL-C >60 mg/dL
- Decrease TG <150 mg/dL
- Control BP
- Stop smoking
- Control diabetes
- Lose weight
- Decrease alcohol
- Increase exercise
- Good diet – whole grains, high fiber, fruits, vegetables, low cholesterol, omega-3 fatty acids