Heart attack. Gross specimen of tissue from a heart where infarction (tissue death, dark areas at upper right and centre left) has taken place. This causes the pain of a heart attack. Tissue death in the heart is usually caused by a blockage of the blood flow in the coronary arteries that supply oxygenated blood to the heart muscle. A heart attack can be rapidly fatal. It is a common cause of death, linked to a sedentary lifestyle, stress, obesity and cigarette smoking. Many people survive if given emergency medical treatment, but lifestyle changes and surgery are often required to prolong life.