Clinical Presentation of Myocardial Ischemia and myocardial blood
flow 2/2
1. IHD: a condition in which there is an imbalance between myocardial oxygen supply and demand
2. what is IHD most often caused by: atherosclerotic disease of coronary arteries
3. what determines myocardial oxygen supply: O2 content
coronary blood flow
4. what determines coronary blood flow: coronary perfusion pressure
coronary vascular resistance
5. what determines myocardial oxygen demand: wall stress
heart rate
contractility
6. what is O2 content determined by: hemoglobin concentration
degree of systemic oxygenation
7. myocardial oxygen extraction: near max at rest
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, 8. how are increases in myocardial oxygen consumption met: with a proportional
increase in coronary blood flow and oxygen delivery
9. perfusion pressures: the majority of coronary blood flow occurs during diastole due to compression of
the branch arteries and arterioles during systole
10. what does perfusion pressure equal: aortic diastolic pressure
11. how does hypotension give supply/demand mismatch: decreases myocardial oxygen
supply
12. how does tachycardia give supply/demand mismatch: leaves less time for diastolic filling
13. what is resistance modulated by: external compression and intrinsic tone
14. external compression affecting resistance: systolic compression of coronary arterials and
increased LV end diastolic pressure
15. types of factors impacting intrinsic tone: metabolic
endothelial
neural
2/5
flow 2/2
1. IHD: a condition in which there is an imbalance between myocardial oxygen supply and demand
2. what is IHD most often caused by: atherosclerotic disease of coronary arteries
3. what determines myocardial oxygen supply: O2 content
coronary blood flow
4. what determines coronary blood flow: coronary perfusion pressure
coronary vascular resistance
5. what determines myocardial oxygen demand: wall stress
heart rate
contractility
6. what is O2 content determined by: hemoglobin concentration
degree of systemic oxygenation
7. myocardial oxygen extraction: near max at rest
1/5
, 8. how are increases in myocardial oxygen consumption met: with a proportional
increase in coronary blood flow and oxygen delivery
9. perfusion pressures: the majority of coronary blood flow occurs during diastole due to compression of
the branch arteries and arterioles during systole
10. what does perfusion pressure equal: aortic diastolic pressure
11. how does hypotension give supply/demand mismatch: decreases myocardial oxygen
supply
12. how does tachycardia give supply/demand mismatch: leaves less time for diastolic filling
13. what is resistance modulated by: external compression and intrinsic tone
14. external compression affecting resistance: systolic compression of coronary arterials and
increased LV end diastolic pressure
15. types of factors impacting intrinsic tone: metabolic
endothelial
neural
2/5
