The symptoms of angina are mainly chest pain, the characteristics of chest pain: 1, the site is mainly in the sternal body after the wave of the precordial area, the range of palm-sized, or even across the forehead, often spread to the left shoulder, the left inner arm, ring finger and little finger or neck, throat, jaw; 2, the nature of the pain is often dull pain for dullness, pressure, tightness, burning, knife-like, drill top-like. Angina attack, patients are often forced to stop the ongoing activities until the symptoms are relieved; 3, the triggering factors, often occurs when physical activity or emotional excitement, sometimes full meals, cold, smoking, tachycardia, shock can also be triggered; 4, the duration, often after the emergence of gradually aggravated, to a certain extent after the duration of 3-5 minutes, rarely more than half an hour; 5. Relief mode generally in the cessation of the original activity or sublingual nitrates and other drugs, can be relieved within a few minutes. Angina can cause abnormal myocardial segmental movement, electrical instability, structural dysfunction of the heart, which can lead to heart failure, arrhythmias, and in severe cases patients can die suddenly. Long-term angina pectoris can cause myocardial hibernation, tonus, fibrosis, and symptoms of chronic congestive heart failure, and sudden death can occur during the course of the disease.