If a pregnant woman has sinus tachycardia in late pregnancy, the first thing to do is to identify the cause of the tachycardia and treat the primary disease in order to better control the tachycardia, such as whether the patient is anxious or tense. It is also possible that the patient is suffering from an ionic disorder, such as hypokalemia, and it is recommended that oral potassium chloride extended-release tablets be administered, and if necessary, intravenous potassium supplementation can be used to correct the ionic disorder. It is also possible that the patient may have perinatal cardiomyopathy or abnormal thyroid function. If the patient is in late pregnancy, it may be necessary to combine treatment with correction of heart failure, and if necessary, drugs such as sodium nitroprusside can be used in combination.