Background：Atrial fibrillation is one of the most common cardiac arrhythmias which has been
received relatively little attention until recently. Despite the variety of treatment modalities including
drugs, surgery, catheter ablation and devices, the overall treatment of atrial fibrillation is not always
satisfactory. Pharmacotherapy is still the most commonly used treatment though the unfavorable side
effects of antiarrhythmic drugs are problematic. The purpose of this study is to compare the efficacy
of class Ic antiarrhythmic drugs, propafenone versus flecainide.
Methods：We treated one hundred eighteen patients with atrial fibrillation by class Ic
antiarrhythmic durgs, propafenone or flecainide with/without DC cardioversion to convert to and
maintain the sinus rhythm. We compared the clinical findings, drug efficacy, side effects of durgs
between two groups.
Results：30 patients were treated by propafenone and 88 patients by flecainide. 21 and 60 patients in
each group were lone atrial fibrillation, 14 and 49 patients were paroxysmal atrial fibrillation. Mean
duration of drug administration were 360.9, 339.4 days, respectively. The convesion rate to sinus
rhythm by drugs was 25.0% in propafenone group and 30.7% in flecainide group(p=NS). The 300
days-manitenance rates of sinus rhythm after conversion by drugs or DC cardioversion were 63.3%,
70.4%(p=NS)respectively.
The side effects of durgs were dizziness, nausea and vomitting in both group and 1st degree AV
block, transient sinus node dysfunction and decreased visual acuity in flecainde group. The drugs
were discontinued in 11(37.7%) and 26(29.5%) patients in each group due to recurrence of atrial
fibrillation or side effects of drugs.
Conclusion：This study suggests that propafenone and flecainide are comparably effective in
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maintaining sinus rhythm in atrial fibrillation patients. Further prospective and large study is required
to confirm this findings.ope
