It is not difficult to identify typical angina pectoris from the characteristics of the trigger, location, nature, duration and mode of relief of chest pain (or chest tightness). However, studies have shown that only 60% of angina pectoris due to ischemia is typical angina, and almost all the rest are atypical chest pain. Because of the diverse clinical symptoms of atypical angina, it is easy to be confused with other diseases, resulting in misdiagnosis or missed diagnosis, or even delayed treatment. For example, some patients only present with palpitations, discomfort in the precordial region, pressure or smothering sensation, or pain in the radiating area only. Some patients complain of tightness or pain in the throat, jaw pain, toothache, neck pain, scapular pain, fingertip pain, abdominal pain, and radiating pain in the upper arm. Elderly people often have atypical symptoms and may only feel chest tightness, shortness of breath and fatigue. Elderly diabetic patients even only feel chest tightness without any obvious chest pain site. So, how to identify angina from a wide range of atypical symptoms? First, carefully understand the characteristics of the symptoms. If some of the features of the patient are typical, angina should not be easily excluded even if some of the features are atypical (especially if the site is atypical). It has been found that angina can radiate to almost any part of the body except the lower extremities (Figure 2). For example, if a patient presents with toothache immediately after activity, even if other features are atypical, angina should be highly suspected and further investigated. For example, if the pain is pins and needles in the chest and lasts only a few seconds, or if there is pressure at the site of pain, angina can usually be quickly ruled out. Second, understand the risk factors and identify patients at high risk of coronary heart disease. For men, over 40 years old, smokers, obese, with diabetes, hypertension, hyperlipidemia and other factors, even if the symptoms are not typical, angina pectoris due to coronary heart disease should be actively ruled out. Third, it is more common for elderly and diabetic patients with atypical symptoms. For example, some elderly patients with angina pectoris attacks can be manifested as shortness of breath after activity, which can be completely without symptoms such as chest tightness and chest pain, and can be easily mistaken for cardiac insufficiency. If the patient has pre-existing reduced cardiac function, the diagnosis is more likely to be missed. Such patients should actively seek medical consultation and have the differential diagnosis made by a professional. Identifying ischemic angina from atypical symptoms is often not an easy task, and even professionals may not be able to make a correct diagnosis immediately. Most patients often need to undergo some special tests (such as exercise test, nuclear, dynamic ECG, coronary CTA, etc.) to further clarify the diagnosis. In order to reduce the number of missed diagnoses and misdiagnoses, it is recommended that patients with atypical symptoms go to a regular hospital for professional consultation as soon as possible to avoid delaying the diagnosis and treatment, resulting in irreversible consequences (such as myocardial infarction or even death).