Causes

Coronary artery disease is thought to begin with damage or injury to the inner layer of a coronary artery, sometimes as early as childhood. The damage may be caused by various factors, including:

• Smoking
• High blood pressure
• High cholesterol
• Diabetes or insulin resistance
• Not being active (sedentary lifestyle)

Once the inner wall of an artery is damaged, fatty deposits (plaque) made of cholesterol and other cellular waste products tend to collect at the site of injury. This process is called atherosclerosis. If the plaque surface breaks or ruptures, blood cells called platelets clump together at the site to try to repair the artery. This clump can block the artery, leading to a heart attack.