Safety of oral propafenone in the conversion of recent onset atrial fibrillation to sinus rhythm:: A prospective parallel placebo-controlled multicentre study

Aim: Oral propafenone is effective in restoring sinus rhythm however the proarrhythmic effects are still unknown. The Safety Antiarrhythmic Therapy Evaluation (SATE) trial was a prospective randomized placebo-controlled multicentre study which evaluated the safety of acute oral loading dose of propafenone in patients with recent onset atrial fibrillation. Secondary end-points were to evaluate the effect of digitalis added to propafenone in ventricular rate control and the efficacy of propafenone alone or added to digitalis compared with efficacy of digitalis plus quinidine. Methods and results: 246 patients (126 male; 58±11 years) with atrial fibrillation of <48 h duration were randomly allocated to one of four groups: digitalis 0.75–1 mg i.v. plus quinidine 1100 mg (D+Q, 70 patients); propafenone 450–600 mg orally (PNF, 66 patients); propafenone 450–600 mg orally plus digitalis 0.750–1 mg i.v. (PNF+D, 70 patients); placebo (Pl, 40 patients). All patients underwent 24-h ECG Holter monitoring. Safety was assessed by evaluating the appearance of adverse events classified as mild, moderate and severe. No severe adverse events were reported. Short lasting asymptomatic atrial flutter episodes with atrio–ventricular conduction ≥2:1 were observed in 14% of the D+Q group, 21% PNF, 18% PNF+D and in 8% Pl. One patient in the D+Q group and four in the PNF+D group showed asymptomatic runs of 3–4 ventricular ectopic beats. Reversible sinus atrial blocks (<3 s) were detected in two patients of the D+Q group and in two of the PNF group. In patients with persistent atrial fibrillation the ventricular rate was similar in the four study groups. At 3 h the high efficacy of propafenone was confirmed. At the 24th hour no differences were found between active treatment and placebo arms. Conclusion: Propafenone in a single oral loading dose is safe and promptly effective in patients with recent onset atrial fibrillation.