Propafenone Dose for Emergency Room Conversion of Paroxysmal Atrial Fibrillation
D. Antonelli, A. Darawsha, S. Rimbrot, N.A. Freedberg, T. Rosenfeld
Dept. of Cardiology and Emergency Room, Central Emek Hospital, Afula
Paroxysmal atrial fibrillation (AF), a frequent cause of repeated hospitalization, is effectively treated with propafenone. The time to conversion to sinus rhythm is a consideration when managing AF in the emergency room. We investigated the conversion rates of paroxysmal AF by 3 different oral propafenone (P) regimens, in terms of time to conversion.
188 patients with onset of AF within 48 hours were treated with propafenone (P): 48 received 600 mg as a first oral dose followed after 8 hrs by 150 mg (Group A); 82 received 300 mg as a first dose, followed by the same dose 3 and again 8 hrs later (B); 58 received 150 mg every 3 hrs, up to a total dose of 600 mg (C). P was stopped when sinus rhythm was achieved.
Rates of conversion to sinus rhythm after 3 hrs in the 3 groups were: 46%, 41% and 26% respectively; after 8 hrs: 77%, 78% and 70%; and after 12 hrs: 81%, 84% and 76%. Treatment was discontinued in 8. There was excessive QRS widening (>25% of the basal value) in 1 in group A, 1 in group B and 2 in group C; wide-QRS tachycardia occurred in 4 in group B. In Group A there was a higher rate of early successful conversion, with a lower incidence of side-effects than with the other regimens.