Regulation of Coronary Blood Flow & Myocardial Oxygen

Blood flow through coronary vasculature is greatest during _________________

Diastole
Why is coronary blood flow greatest during diastole? (3)
- Partial occlusion of coronary artery from aortic valve cusps
- Compression of intramyocardial coronary vessels during systole (dilation during diastole)
- Reactive hyperemia
What is reactive hyperemia?

Increasing blood flow following a period of occlusion
True or false. The heart cannot really increase the amount of oxygen extracted from arterial blood.

True
What does the heart do to match an increased myocardial oxygen demand?

Increases coronary blood flow
What are the factors that affect myocardial oxygen supply?
- Patency of coronary vessels
- Ventricular wall compression
- Diastolic filling time
What are the factors that affect myocardial oxygen demand?
- Heart rate
- Myocardial contractility
- Afterload
What are the significant contributors to afterload?

Ventricular pressure and thickness of wall
How does ANS modulate coronary blood flow?
- Alters coronary vascular resistance (directly)
- Alters heart rate and therefore metabolic activity (indirectly)
Coronary blood flow is modified primarily by ________________

Myocardial metabolic activity
Compare and contrast the volume work of the left and right ventricles

Same for both
Compare and contrast the pressure work of the left and right ventricles

Pressure work is higher in left (aorta)

Author

stepha998

344654

Card Set

Regulation of Coronary Blood Flow & Myocardial Oxygen

Description

ATSU

Updated

2019-01-15T07:29:30Z

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