Influence of an antiarrhythmic premedication on the development of premature ventricular contractions during fiberoptic gastroduodenoscopy.

Heart rate, blood pressure and ECG changes during fiberoptic gastroscopy were examined in 128 patients, 60 of whom had been orally premedicated with Mexiletine. 55% of the non-premedicated patients developed occasional, and 22% of this group developed accumulated or frequent, premature ventricular contractions. In the patient group with antiarrhythmic premedication, the respective figures were 25% and 8%, and in this group patients with a normal ECG developed premature ventricular contractions less frequently than patients with pathological changes in the ST segment. The antiarrhythmic premedication had no influence on pulse or blood pressure.