ECG is the abbreviation of electrocardiogram, which includes many items, their specific normal values are as follows: 1, the height of P wave should be below 2mm; 2, the PR interval should be between 0.12-0.20s; 3, the time limit of QRS should be about 0.11s; 4, the ST segment is generally level with the TP segment, that is, the ST segment should be level with the baseline, ST segment elevation or ST segment depression The height of the T wave is less than 1/4 of the R wave, but if the T wave is elevated without ST segment change, the clinical significance is not great.