What is the main difference between angina pectoris and myocardial infarction?

Angina pectoris is related to myocardial ischemia induced by coronary heart disease and other factors. Its pain site is at the upper part of sternum, showing crushing and asphyxiating pain, lasting for about 5 minutes, which can be relieved by rest or taking drugs. Myocardial infarction is related to metabolic disorder and genetic factors of the body; its pain site is behind sternum, and the pain lasts for a long time, usually about 15 minutes; taking drugs or rest cannot alleviate it.