An angina is chest pain caused by reduced flow of blood to the heart muscle. It is not a heart attack, but may be a warning of an impending heart attack. Angina specifically occurs when the heart muscle is not receiving enough oxygen, and coronary artery disease causes chest pain. With angina, however, no permanent damage is done to the heart muscle. Approximately 6.2 million people in the U.S. have been diagnosed with angina. The symptoms of angina are similar to those of a heart attack. They are most commonly described as a squeezing, burning, tightness, fullness, or pressure across the chest.