Coronary artery disease—known as CAD for short—affects more than 15 million American adults, making it the most common type of heart disease. It's also the leading cause of death in men and women in the United States.
But because CAD usually progresses over many decades, you may not know you have it until it starts causing symptoms.
CAD develops when your coronary arteries, which act like fuel lines to supply blood to the heart, become damaged or diseased. Most often, CAD develops from a buildup of plaque—fat, cholesterol, collagen, inflammatory cells and other substances—that collect in the walls of the coronary artery, which is called atherosclerosis.
Over time, this plaque can calcify and harden, and the arteries can become narrow or blocked. When this happens, blood supply to the heart becomes restricted. As a result, the heart doesn't get the oxygen and nutrients it needs. This can lead to chest pain, heart attack, heart failure and some heart rhythm problems. CAD is sometimes called atherosclerotic heart disease or coronary heart disease.