ECG inversion is a change in ECG vectorology that occurs when the human body describes and traces the ECG, usually with ST-segment inversion as the main clinically representative figure, and it is called electrocardiographic inversion when the ST-segment produces inversion, and it is due to the following factors: firstly, psychological and physiological factors, for example, when the patient is overly nervous or experiences sympathetic over-excitement, for example, when he/she is angry, anxious, impatient, or extremely fearful, it will such typical changes in the electrocardiogram occur. Secondly, in some pathological factors, such as in unstable angina pectoris in coronary atherosclerotic heart disease, in acute coronary syndromes, or in severe myocarditis, pericarditis, or hypertrophic obstructive cardiomyopathy, ECG inversion can occur. Then, ECG inversion can also occur in severe ionic disorders, such as hypokalemia. Finally, endocrine metabolic disorders, such as thyroid dysfunction, can also occur.