Atrial fibrillation and the pharmacological treatment: the role of propafenone.

BACKGROUND Atrial fibrillation is the most frequent cardiac rhythm disturbance, with prevalence increasing with age. This disease is a major risk factor for ischaemic stroke. The costs resulting from atrial fibrillation are really impressive. Pharmacological agents are the first line therapy for the management of atrial fibrillation. Antiarrhythmic drugs are used to terminate arrhythmias, as acute treatment for conversion of recent onset atrial fibrillation, and to maintain sinus rhythm, as chronic therapy for prevention of atrial fibrillation recurrences. Among antiarrhythmic agents, drugs that inhibit early sodium current (as propafenone) are proven effective in atrial fibrillation. In this review, the most relevant data on propafenone are provided. DISCUSSION The development of a sustained-release formulation of propafenone allowed to reduce the wide fluctuations in plasma levels observed with the immediate release preparation, improving compliance and adherence to therapy, by simplifying the dosing regimen from 3 to 2 daily doses. Propafenone resulted an effective measure as acute treatment for conversion of recent onset atrial fibrillation, and to maintain sinus rhythm, as chronic therapy for prevention of atrial fibrillation recurrences. In several clinical studies, strong increases of arrhythmia-free periods as well as marked increases in time to recurrence of symptomatic atrial fibrillation, such as paroxysmal supraventricular tachycardia and paroxysmal atrial fibrillation were observed. In particular, well-designed clinical studies demonstrated in large patient populations the efficacy of propafenone at several doses. At the suggested doses propafenone is usually well tolerated. CONCLUSION The risk of increased occurrence of regular supraventricular arrhythmia or paroxysmal supraventricular tachycardia has been overestimated for propafenone, because this adverse event was seen in all treatment groups, including placebo, with the same (and low) frequency.