The blood flow volume and the oxygen absorption of cardiac muscle is high. To a 70kg weight person, the total blood flow volume of cardiac muscle is equal to 250ml/min, which is about 5% of cardiac output. The cardiac muscle oxygen requirement is high, which is 10 times of average oxygen demand for the whole body tissue. The artery blood oxygen capacity approximately is 20ml%. After the blood flows through the cardiac muscle, about 70% oxygen is ingested by cardiac muscle. While, ordinary tissue only absorb 22% oxygen quantity from the artery blood. This is because all the energy the heat's activities need is almost completely supplied by the aerobic metabolism. Even under the peaceful condition, the cardiac muscle also nearly absorbs the maximum oxygen from the artery blood.

Once the myocardial ischemia (or oxygen deficit), or the oxygen consumption of the cardiac muscle increases, it can only depend on the increase of blood stream volume in the coronary artery to satisfy the oxygen demand of cardiac muscle.

In the normal condition, the coronary circulation has large store capacity. Its blood flow volume can have the remarkable change along with body's physiological situation. When strenuous exercise happens, the coronary blood stream quantity is 6~7 times than the body rests. When oxygen deficit occurs, the coronary artery expands; the blood flow volume will increase 4~5 times. When coronary atherosclerosis lead to narrow or blocking coronary artery, or when the coronary artery have the convulsion, the coronary artery cannot have compensation expand, then there is contradiction between the cardiac muscle blood stream supply and demand, thereupon it will cause the angina pectoris, even myocardial infarction.

Understand the oxygen absorption of cardiac muscle! edited by Heart Problems, all rights reserved, Do not copy or revise without our permission.