|Coronary artery disease, also called coronary heart disease. Heart disease is a result of plaque buildup in your coronary arteries -- a condition called atherosclerosis -- that leads to blockages. The arteries, which start out smooth and elastic, become narrow and stiff. This is the first stage in the development of plaque, causing the arteries to become rigid, restricting blood flow to the heart. The heart potentially beomes starved of oxygen. The most concerning part of coronary artery disease is that the plaque could rupture, leading to a heart attack and potentially sudden cardiac death.