Factors disturb the balance between oxygen demand and delivery Demand v Preload (venous return Y Afterload (arteriolar resistance) Heart rate D elIve Atherosclerosis plaque Thrombus Y Spasm of coronary arteriesDemand ✓ Preload (venous return ) ✓ Afterload (arteriolar resistance) ✓ Heart rate Delivery ✓ Atherosclerosis plaque ✓ Thrombus ✓ Spasm of coronary arteries 9 Factors disturb the balance between oxygen demand and delivery