Coronary artery disease (CAD) is caused by the narrowing of the small blood vessels that supply oxygen and blood to the heart. It's most common cause is atherosclerosis, a buildup of plaque in the walls of the arteries.
CAD can cause chest pain, shortness of breath, heart attack, and other symptoms that typically occur on exertion. High cholesterol, diabetes, and high blood pressure all contribute to CAD. It is the leading cause of death for both men and women in the United States.