heart and blood vessel disorders
Angina
Causes of Angina
The heart muscle needs a constant supply of oxygen-rich blood. The Blood Supply of the Heart , which branch off the aorta just after it leaves the heart, deliver this blood. Usually, angina occurs when the heart’s workload (and need for oxygen) exceeds the ability of the coronary arteries to supply an adequate amount of blood to the heart. Coronary blood flow can be limited when the arteries are narrowed (see When angina is due to atherosclerosis, it usually first occurs during physical exertion or emotional distress, which make the heart work harder and increase its need for oxygen. If the artery is narrowed enough (usually by more than 70%), angina can occur even at rest, when the demands on the heart are at their minimum. Severe Overview of Anemia increases the likelihood of angina. In anemia, the number of red blood cells (which contain hemoglobin—the molecule that carries oxygen) or the amount of hemoglobin in the cells is below normal. As a result, the oxygen supply to the heart muscle is reduced. 