Myocardial injury can be caused by many reasons, such as myocardial infarction, myocarditis, etc. Patients often have abnormal cardiac symptoms, but due to the different progress of the disease, the specific symptoms vary somewhat and cannot be generalized. If the patient’s condition is mild and the myocardial injury is not serious, he or she may experience chest pain, panic, shortness of breath, dyspnea, blackness in front of the eyes, weakness of the limbs and other uncomfortable symptoms. In addition, if the myocardial injury is caused by myocardial infarction, the chest pain manifests as crushing pain or colic, which usually lasts for more than 30 minutes, and the site of this chest pain is often located in the left precordial region, which is palm-like in size, or can be located in the posterior or inferior sternum, while the patient often has sweating and a sense of near death. If the patient’s condition is more severe, the heart muscle is severely damaged, and the ejection capacity of the heart is significantly reduced, the patient’s discomfort symptoms are aggravated at this time, and even fainting and sudden death occur. When patients have symptoms of discomfort, they should immediately consult a doctor for laboratory tests such as troponin and cardiac enzyme profile, and the diagnosis will be confirmed by the test results combined with clinical symptoms for further treatment.