level: Arteries and Coronary Circulation
Questions and Answers List
level questions: Arteries and Coronary Circulation
| Question | Answer |
|---|---|
| What are the key features of the arterial system? | Resistance is defined as the impediment to blood flow in a vessel. It can be increased with vasoconstriction and decreased with vasodilation. Conductance is the measures of blood flow for a given pressure difference. Conductance is the reciprocal over resistance where: Conductance = 1/Resistance |
| What are the principles of flow and pressure regulation in the circulation? | Pressure pulsations - |
| Describe the coronary metabolism in regards to coronary circulation | Myocardial ATP production is ~95% from metabolism. Resting myocardial energy demand is approximately 20-fold that of skeletal muscle. To maintain O2supply, O2extraction in cardiac tissue is ~75%. As a result, increase in O2demand during exercise are mediated primarily by increases in coronary blood flow |
| Describe the coronary blood flow in regards to coronary circulation | Opposite pattern – flow occurs in diastole rather than systole. Primarily due to compression of epicardial arteries during ventricular contraction. |
| Describe the control of coronary blood flow in regards to coronary circulation | Regulated in proportion to oxygen demand During periods of high demand, coronary blood flow is matched to demand via the release of vasodilatory substances and nervous system control (autonomic NS) |