atherogenesis

Question 1

factors leading to endothelial cell dysfunction

Answer 1

hypercholesteremia
HTN
diabetes
obesity
smoking
physical injury to ECs
transplant rejection

Question 2

how much do known, modifiable risk factors contribute to population-attributable risk for MI

Answer 2

90% for men

94% for women

Question 3

what is dyslipidemia

Answer 3

high LDL-C, low HDL-C

Question 4

main component of LDL-C

Answer 4

apolipoprotein B

Question 5

main component of HDL-C

Answer 5

apolipoprotein A-1

Question 6

what is the strongest modifiable predictable risk for MI

Answer 6

ratio of apoB/apoA

(want it to be low indicating high apoA)

no therapeutic method to increase HDL levels but can decrease LDL levels

Question 7

change in MI risk due to diabetes

Answer 7

diabetics have 2-4 X higher risk of MI

Question 8

why does diabetes affect MI risk?

Answer 8

mostly due to abnormalities in lipid levels seen in diabetics

Question 9

what is the relationship between abdominal obesity and atherogenesis

Answer 9

visceral fat releases more inflammatory factors than subcutaneous fat outside the abdomen

Question 10

what 9 risk factors account for 90%/94% (men versus women) of population attributable risk for MI

Answer 10

1. ApoB/ApoA1 *** best
2. smoking
3. psychosocial
4. diabetes
5. HTN
6. abdominal obesity
   these are in descending order of those that increase risk for MI

the following decrease risk for MI starting with the least helpful

1. regular alcohol consumption
2. regular physical activity
3. daily consumption of fruits and veg

Question 11

what can affect myocardial O2 supply and demand

Answer 11

1. HR and diastolic time
2. systolic and diastolic arterial pressured
3. coronary resistance and coronary perfusion gradient
4. LV end diastolic pressure (preload)
5. LV wall thickness
6. LV wall stress and law of LaPlace (P X R/2h)
7. exercise

Question 12

why does diastolic time matter in O2 supply and demand to the myocardium

Answer 12

coronary flow occurs mostly/only in diastole–> therefore, longer diastolic time allows more supply to the heart cells

this is one of the reasons beta blockers are used to treat ischemia because they slow the HR and increase diastolic time

Question 13

what is the equation for coronary perfusion gradient?

Answer 13

coronary perfusion gradient = aortic root pressure - LV pressure

during systole the aortic root pressure and LV pressure are equal and therefore the perfusion gradient is 0 and there is no flow into the coronary arteries

in diastole, the aortic root pressure is much higher than the intraventricular cavity pressure and so blood flows into the coronary arteries