Heart attack is common in the middle-aged and elderly population with severe stenosis of coronary arteries, and the typical symptoms before the onset are angina, dyspnea, etc. Individual patients may have atypical symptoms such as headache and toothache. If patients with coronary artery disease suddenly experience chest pain and discomfort, they need to seek timely medical consultation for early diagnosis and early treatment.1. Typical symptoms: angina pectoris is a typical signal before the occurrence of heart attack, which can appear under emotional excitement, exertion or activity, anger and other states. The pain can be accompanied by chest tightness, panic attacks, difficulty in breathing, and pain radiating to the left arm, shoulder, back, neck and gums. This pain can be recurrent, appearing during emotional excitement and exertion, and the symptoms will be reduced after the trigger disappears; 3. Non-specific symptoms: some patients have headache, toothache, abdominal pain, weakness, jaw pain, burning sensation in the throat, coughing frothy sputum, and non-specific symptoms such as pain under the fenestra before the heart attack, so patients with special physique and other chronic diseases should pay more attention to these problems in general to avoid delaying treatment . Patients with heart attack have obvious chest pain at the onset, and it lasts for a long time. Patients may have clinical manifestations such as heavy sweating, inability to lie down, difficulty in breathing and irritability, and the symptoms cannot be significantly relieved after rest or nitroglycerin. Patients with severe coronary artery stenosis should always have nitroglycerin, aspirin, clopidogrel and other drugs at home, and take them in time when the heart attack occurs, which can buy time for treatment.