"Coronary heart disease (CHD), also commonly referred to as just heart disease, is a common term for the buildup of plaque in the heart’s arteries that could lead to heart attack. Health professionals frequently use the terms coronary heart disease and coronary artery disease interchangeably. However, coronary heart disease, or CHD, is actually a result of coronary artery disease, or CAD. With coronary artery disease, plaque first grows within the walls of the coronary arteries until the blood flow to the heart’s muscle is limited. The coronary arteries are the blood vessels that supply blood to your heart. They branch off of the aorta at its base. The right coronary artery, the left main coronary, the left anterior descending, and the left circumflex artery, are the four major coronary arteries. Blockage of these arteries is a common cause of angina, heart disease, heart attacks and heart failure. This restriction of the blood supply to the tissues is also called ischemia. It may be chronic, narrowing of the coronary artery over time and limiting of the blood supply to part of the muscle. Or it can be acute, resulting from a sudden rupture of a plaque and formation of a thrombus or blood clot."