Coronary heart disease (or coronary artery disease) is a narrowing of the small blood vessels that supply blood and oxygen to the heart (coronary arteries). Coronary disease usually results from the build up of fatty material and plaque (atherosclerosis). As the coronary arteries narrow, the flow of blood to the heart can slow or stop. The disease can cause chest pain (stable angina), shortness of breath, heart attack, or other symptoms.

Coronary heart disease (CHD) is the leading cause of death in the United States for men and women. According to the American Heart Association, about every 29 seconds someone in the US suffers from a CHD-related event, and about every minute someone dies from such event. The lifetime risk of having coronary heart disease after age 40 is 49% for men and 32% for women. As women get older, the risk increases almost to that of men. (See also Heart disease and women.)

There are many factors which increase the risk for CHD. Some of the risks are based on family history (genetics), and others are more controllable. Risk factors include the following:

• Family history of coronary heart disease (especially before age 50)
• Male gender
• Age (65 and greater)
• Tobacco smoking
• High blood pressure
• Diabetes
• High cholesterol levels (specifically, high LDL cholesterol and low HDL cholesterol)
• Lack of physical activity or exercise
• Obesity
• High blood homocysteine levels
• Menopause in women
• Infection that causes inflammatory response in the artery wall. (There is some evidence that suggests this, but the theory is being studied.)