Coronary artery disease is the progressive narrowing of the coronary arteries, usually due to a build up of fatty plaques along the vessel walls. It's the most common cause of heart disease in the United States. When the heart is deprived of blood, it fails to receive sufficient oxygen. Because the heart must be nourished with a constant flow of oxygen and nutrient-rich blood, damage occurs when it no longer receives the supply it needs. The first sign of coronary artery disease may be in the form of chest pain, called angina (an-JIE-nuh). This appears as a severe, crushing pain that may radiate from the chest to the left arm, lower jaw, and shoulder blade. Shortness of breath may also occur. Angina usually occurs after physical exertion, as a result of emotional excitement, or exposure to cold. If a coronary artery becomes completely blocked, a heart attack may occur. Factors that lead to coronary artery disease include high blood pressure, diabetes, smoking, obesity, and a family history of heart disease. For more information about coronary artery disease, contact your health care provider.