Treatment of Atrial Arrythmias After Cardiac Surgery With Intravenous Disopyramide

Summary The aim of this study was to investigate the efficacy of intravenous disopyramide in patients with persistent atrial tachyarrhythmias after open‐heart surgery. Thirty patients whose arrhythmia persisted more than four hours after an initial bolus of intravenous digoxin 0–75 mg were randomly assigned to two groups (15 in each group). One group was given a further 12 hr of intravenous digoxin therapy, and the second was given 12 hr of intravenous disopyramide as a loading dose (2 mg/kg) followed by a constant infusion. Patients who had not reverted 12 hr after randomisation were “crossed‐over” to the alternate therapy for 12 hr. Of the 25 patients eventually given disopyramide for a 12‐hr period, 17 returned to sinus rhythm during that period (68%) and 13 of these reversions occurred within the first hour. These results were significantly better (P < 0–01) than for the 21 patients given 12 hr of digoxin therapy of whom only five reverted (none within one hour). It is concluded that intravenous disopyramide administered after a loading dose of digoxin is an effective therapy for postoperative atrial arrhythmias.