Guidelines for the use of propafenone in treating supraventricular arrhythmias.

Propafenone is a sodium channel blocking agent with a mild beta- and calcium channel-blocking activity. Several controlled and noncomparative studies have documented its efficacy in a variety of supraventricular arrhythmias in both adults and children. Propafenone is comparable with other Vaughan-William class I antiarrhythmic drugs for acute conversion of atrial fibrillation. It is also comparable with other drugs for prevention of recurrences in paroxysmal atrial fibrillation and for maintenance of sinus rhythm following successful cardioversion of chronic atrial fibrillation. Although propafenone is effective in the acute management of junctional reentrant tachycardias, the availability of safer drugs precludes its routine use for these arrhythmias. It may, however, be preferred for the acute management of haemodynamically well tolerated pre-excited atrial fibrillation in patients with the Wolff-Parkinson-White (WPW) syndrome. It also has documented efficacy in the long term therapy of patients with junctional tachycardias, and is a useful first-line drug in the management of arrhythmias in patients with the WPW syndrome, particularly when there is a short anterograde refractory period of the accessory pathway. Noncomparative studies were confirmed good efficacy and tolerability of propafenone in the short and long term management of paediatric supraventricular arrhythmias. It seems to be particularly effective for the treatment of ectopic atrial and junctional tachycardias, which are generally difficult arrhythmias to manage. Propafenone appears to have an acceptable adverse effect profile during both short and long term therapy. As with most other antiarrhythmic agents, there is a proarrhythmic potential. This has also been observed in children. There is a theoretical possibility that the beta-blocking properties of propafenone may protect against its proarrhythmic potential. However, this has not been confirmed in clinical studies. In conclusion, propafenone appears to be effective in the management of a wide spectrum of supraventricular arrhythmias. It should be considered among the first line drugs for management of these arrhythmias in patients without structural heart disease.