Coronary heart disease is a series of clinical conditions caused by atherosclerosis resulting in narrowing of the lumen of the coronary arteries, which leads to insufficient blood supply to the heart muscle. It includes angina pectoris, myocardial infarction, heart failure, arrhythmia and sudden death. Wu Yongjian, Department of Cardiovascular Medicine, Fu Wai Hospital, Beijing, China The coronary artery is located on the surface of the heart and is a blood vessel dedicated to supplying blood to the heart muscle itself. It is divided into two left and right ones. The left side is the left main trunk and the right side is the right coronary artery. The left main trunk is further divided into the left anterior descending branch and the left gyrus branch. Left anterior descending branch