Coronary heart disease is the abbreviation for coronary atherosclerotic heart disease. It occurs when coronary arteries undergo atherosclerosis, causing narrowing or blockage of the lumen, leading to myocardial ischemia, hypoxia, or necrosis. After the diagnosis of heart disease, if conservative treatment or coronary intervention is administered, then it falls under the category of cardiology. However, if coronary heart disease is diagnosed and further treatment necessitating bypass surgery is needed, then a cardiac surgeon should perform the surgery.