What Causes Angina?

Angina is caused by insufficient blood flow to the heart during times of increased oxygen demand by the heart.

The heart has a limited ability to increase its oxygen intake during episodes of increased demand. Therefore, an increase in oxygen demand by the heart (e.g., during exercise or during times of stress) has to be met by a proportional increase in blood flow to the heart.

If at any time there's a reduction of blood flow to the heart caused by the stenosis or spasm of the heart's arteries, or if there's resistance in the coronary arteries, or there's a reduction in the oxygen-carrying capacity of the blood Myocardial ischemia can result, Causing "Angina Pectoris" which is Latin for "Chest Constriction".

Although Atherosclerosis or coronary artery disease, narrowing of the blood vessels is the most common cause of stenosis of the heart's arteries and, hence, angina pectoris. There are other causes of angina in people with normal or minimal narrowing of heart arteries. this can be caused by other types of resistance of the arteries, abnormal constriction or deficient relaxation of heart vessels.

Myocardial ischemia also can be the result of factors affecting blood composition, such as reduced oxygen-carrying capacity of blood, as seen with severe anemia, low number of red blood cells, or long-term cigarette smoking.