Contractile AV State Oxygen Difference OXYGEN OXYGEN Heart DEMAND SUPPLY Regional Rate Myocardial ≠ Distribution Wall Coronary Tension Blood ISCHEMIA Flow Ventricular Coronar Aortic Pressure Volume Vascular Resistance Pressure 影响心肌耗氧量及供氧量的因素影响心肌耗氧量及供氧量的因素