COMPARISON BETWEEN PROPAFENONE AND DIGOXIN ADMINISTERED INTRAVENOUSLYTO PATIENTS WITH ACUTE ATRIAL-FIBRILLATION

in recent-onset atrial fibrillation, intravenous propafenone has been shown to effectively restore sinus rhythm, whereas the efficacy of int ravenous digoxin has been questioned. We directly compared these 2 dru gs and placebo in acute atrial fibrillation. One hundred twenty-three patients with atrial fibrillation lasting <72 hours were randomized to a 10-minute intravenous infusion of either propafenone (2 mg/kg, 41 p atients) or digoxin (0.007 mg/kg, 40 patients) or placebo (42 patients ). After 1 hour, nonconverted propafenone or digoxin patients were swi tched to the alternative drug, while nonconverted placebo patients wer e randomized to either propafenone or digoxin. The observation time en ded 1 hour later. By 1 hour, conversion rates were 49% in the propafen one group, 32% in the digoxin group (p = 0.12), and 14% in placebo gro up (p <0.001 vs propafenone, p = 0.08 vs digoxin). After crossover, di goxin converted 5% of propafenone patients, while propafenone converte d 48% of digoxin patients (p <0.05). In the 36 nonconverted placebo pa tients, sinus rhythm was obtained in 53% of cases with propafenone, an d in 5% with digoxin (p <0.05). Globally, among the 116 patients who r eceived a drug as first treatment, 30 of 60 patients (50%) were conver ted by propafenone versus 14 of 56 (25%) by digoxin (p <0.01) (odds ra tio 2.0, 95% confidence interval 1.19 to 3.36). In nonconverters, the ventricular rare reduction was faster (15 vs 45 minutes) and more prom inent (-24% vs -14%) with propafenone than with digoxin. In conclusion , intravenous propafenone terminates atrial fibrillation more effectiv ely than either placebo or intravenous digoxin. In addition, in noncon verted patients, it obtains a more rapid and marked control of the ven tricular rate. (C) 1998 by Excerpta Medica, Inc.