Low level of TV3V4 on ECG refers to the presence of low level of T wave in leads V3 and V4 of ECG, which may be caused by insufficient blood supply to the myocardium, or it can be found in normal population. 1. Normal population: T-wave is a waveform reflecting the repolarization process of the ventricle, usually in the same direction as the main wave. If there is only a low T wave in leads V3 and V4, and there is no obvious discomfort, no special treatment is needed. 2. Insufficient myocardial blood supply: If there are both V5 and V6 lead T-wave flattening and inversion or V1 lead T-wave upright is larger than V5, it is considered to be caused by coronary heart disease, myocardial ischemia and other heart problems. If there are V3, V4 lead T wave flattening, it is recommended to go to the cardiology department of the hospital for further examination, such as cardiac ultrasound, dynamic electrocardiogram, etc., to clarify the cause of flattening, and the specific diagnosis and treatment should be in accordance with the doctor’s advice.