1.Sudden onset of crushing pain, tightness, suffocation, burning pain, and heavy chest pressure in the upper middle part of the sternum, pain in the lower 1/3 of the sternum, i.e., between the midline of the thorax and the left nipple. 2.The range of angina pain is often a patch, and patients usually use a clenched fist placed in the middle of the chest or slightly to the left to indicate the range of pain. 3, the pain is often not limited to the chest, but also often radiates to the front of the neck throat and other places, and feels like the neck is being strangled. The pain also radiates to the ulnar side and back of the left upper limb, to the left shoulder, the three fingers on the inside of the left hand, and to the legs. It may be accompanied by sympathetic excitation manifestations such as increased heart rate, increased blood pressure, sweating and fear. 4, angina pectoris often starts slowly, with a mild vague pain at first, which can reach a climax after a few minutes. 5, angina pain lasts 3-4 minutes, up to 15 minutes. 6, angina can be triggered by emotional excitement or exertion. 7, angina induced by physical activity, can disappear within seconds after stopping the activity. 8, angina attack should not lie down, lying down when the lower extremity blood flow back to the heart blood volume increased, the heart burden increased, and the angina increased. Patients should rest in a semi-recumbent position. 9, full meals can often trigger angina, and often occur within 30 minutes of eating. Drinking cold water, drunkenness, smoking can also aggravate angina.