Propafenone is a potent antiarrhythmic agent effective in either supraventricular or
ventricular tachyarrhythmias. For proper utilisation, some important pharmacological aspects must be considered, such as nonlinear pharmacokinetics, inability in some patients (poor
debrisoquine metabolisers) to oxidise the
drug in the liver, existence of at least one active metabolite (5-hydroxy-propafenone) and ability to exert a slight beta-blocking activity. Like all the other
antiarrhythmic drugs,
propafenone may be associated with adverse effects and may exert proarrhythmic effects. For this reason, its usage must be based on a careful analysis of the risk-benefit ratio, by considering the patient's profile as well as the characteristics of the
arrhythmia and its prognostic significance.
Propafenone appears to be very effective, and has a favourable risk-benefit profile in the treatment of all supra-ventricular arrhythmias. Particularly, it is effective in converting
atrial fibrillation to sinus rhythm and in preventing
atrial fibrillation recurrences, and is very effective in the pharmacological control of the arrhythmias of the
Wolff-Parkinson-White syndrome.
Propafenone is also effective in suppressing
ventricular premature complexes and
nonsustained ventricular tachycardias. However, because of potential proarrhythmic effects, its use in these arrhythmias must be considered after a careful analysis of the risk-benefit profile, which could be favourable in some patients, but less favourable in others (e.g. patients with
coronary artery disease and
ventricular dysfunction). In malignant ventricular arrhythmias, further studies are needed to define the limitations of
antiarrhythmic drugs in comparison with non-pharmacological treatments, mainly cardioverter/
defibrillators. At present, like the other class I antiarrhythmic agents,
propafenone does not seem to be a first choice prophylactic agent for malignant ventricular arrhythmias, although more data from controlled studies are needed.