Sinus tachycardia with a rightward deviation of the electrical axis is normal if it is caused by physiological factors, and abnormal if it is caused by pathological factors. 1. Normal: Sinus tachycardia may occur when people are exercising, sleep deprived or emotionally excited. Other related checks are fine and there is no underlying disease, there is no need to be overly concerned, increase nutrition in the daily diet, do not stay up late, through daily habits slowly improve. 2. Abnormal situation: patients with heart failure may have left posterior branch block, resulting in sinus tachycardia and right deviation of the electrical axis; chronic pulmonary heart disease, acute pulmonary embolism patients may also have sinus tachycardia and right deviation of the electrical axis; and long-term chronic bronchitis patients, triggered by emphysema, resulting in the enlargement of the right heart and the emergence of pulmonary heart disease, may also appear in this situation. If sinus tachycardia and right deviation of the electrical axis, it is recommended to go to the hospital in a timely manner to improve the relevant examination, and if necessary, follow the doctor’s instructions to standardize the treatment.