Myocardial damage refers to the damage or even necrosis of the patient’s cardiomyocytes. Myocardial damage usually leads to impaired conduction function of the patient’s heart, ischemia of the heart, cardiac hypertrophy and so on. 1. Impaired conduction function: patients often have arrhythmia, conduction block, and may have weakness, palpitations, dizziness and other manifestations, affecting the patient’s life and work, and in serious cases, fainting or even sudden death may occur. 2. Cardiac ischemia: myocardial damage causes cardiac ischemia, which is manifested by nausea, vomiting, stuffiness and pain in the precordial area. 3. Cardiac hypertrophy: myocardial damage causes changes in the structure and function of the heart, leading to cardiac failure, dyspnea and endangering the patient’s life. The harm of myocardial damage is wider, patients should pay attention to it, it is recommended that under the guidance of doctors according to different causes of clear diagnosis, symptomatic treatment.