How long to stop taking Mesylate is determined by the patient’s symptoms and the number of premature ventricular beats on the patient’s 24-hour ECG, and how long to take it or to reduce the dosage and stop taking it. If the number of ventricular premature beats is less than 300 in 24-hour ECG, you can stop the medication and replace it with a beta-blocker to maintain the patient’s heart rate. If the heart rate is more than 300 beats and the patient’s symptoms are more obvious, you should give the patient two tablets orally, two times a day or one tablet, three times a day to maintain the patient’s heart rate, and give the patient a repeat examination of the 24-hour ECG after eating for one to two weeks. If the dynamic electrocardiogram shows a significant reduction in the number of premature ventricular beats or even the disappearance of the number of premature ventricular beats, you can consider discontinuing the treatment of mesylate, and use beta-blockers to maintain the treatment.