Heart ischaemia. Artwork of a heart showing areas affected by ischaemia, the lack of blood to a tissue. The area affected by ischaemia is shown as a white ring at lower right. Muscle damaged by the lack of oxygen-rich blood is shown as an orange ring within the area of ischaemia. Dead muscle tissue is shown as the dark red area at the centre of the damaged muscle. When heart muscle dies, it is known as myocardial infarction, or a heart attack. This causes crushing chest pain, and may be fatal. Heart attacks commonly result from a blockage in one of the coronary arteries which provide the heart with its blood supply.