[Persistent atrial flutter induced by propafenone (Rytmonorm)].

The case history of two patients with atrial fibrillation are presented. In order to prevent/terminate fibrillation propafenone (Rytmonorm, 450-600 mg/day) was started, however this therapy resulted in permanent atrial flutter of 230-270/min mainly with 2:1 antrioventricular conduction. Analyzing the cases the authors emphasize that although Class Ic antiarrhythmic drugs (flecainide, encainide, propafenone) are capable to prevent or terminate atrial fibrillation, they may also induce atrial flutter in approximately 3.5-5% of these patients. The mechanism and recognition of this atrial proarrhythmic action are discussed.