T-wave abnormalities are T-wave hyperacuity, T-wave hypoplasia and T-wave inversion on the ECG. Hyperacute T waves are usually seen in the hyperacute phase of myocardial infarction or hyperkalemia, while low T waves are usually seen in myocardial ischemia, and the presence of a U-wave tends to represent hypokalemia, while inverted or bi-directional T-waves usually represent the possibility of myocardial ischemia. Abnormal T wave may be myocardial ischemia, if the patient has prolonged myocardial ischemia, there will also be chest tightness, shortness of breath, dizziness, and some people will have palpitations, it is recommended to go to the regular hospital in time, and carry out the relevant examination. Relying only on the T-wave abnormality on the electrocardiogram does not determine which disease it is, but also requires the patient to go to the cardiovascular department of the hospital in time, to carry out the relevant examinations, and to clarify the cause of the disease.