Randomised double blind trial of oral versus intravenous flecainide for the cardioversion of acute atrial fibrillation

OBJECTIVE To investigate whether an oral loading dose of flecainide is as safe and effective as intravenous flecainide for the cardioversion of acute atrial fibrillation. DESIGN Prospective, randomised, double blind, double placebo study. SETTING Cardiac care unit of a large district general hospital in the UK. PATIENTS AND METHODS 79 patients presenting with symptomatic acute atrial fibrillation: patients were given either intravenous flecainide (n = 39) or a solution of oral flecainide (n = 40), with appropriate placebos. All patients were heparinised during the study. PRIMARY OUTCOME MEASURES Safety; mean time to cardioversion; proportion of patients restored to sinus rhythm at two hours and eight hours after treatment. Analysis was by intention to treat. RESULTS There were no differences in baseline characteristics between the oral and intravenous groups. Both forms of flecainide were well tolerated, with no adverse clinical events during the study. The mean time to cardioversion was 110 minutes in the oral group and 52 minutes in the intravenous group (p = 0.002). Two hours after treatment, 27 of the 40 patients in the oral group (68%) and 25 of the 39 in the intravenous group (64%) had reverted to sinus rhythm (p = 0.74). Eight hours after treatment, 30 patients in the oral group (75%) and 28 in the intravenous group (72%) had reverted to sinus rhythm (p = 0.76). CONCLUSIONS Intravenous flecainide restored sinus rhythm more rapidly than oral flecainide, but at two hours and eight hours after treatment there was no difference in the proportion of patients cardioverted by the two approaches. These results suggest a role for oral loading doses of flecainide in the treatment of acute or symptomatic paroxysmal atrial fibrillation.

[1]  P. Petersen,et al.  Atrial fibrillation--a review of course and prognosis. , 2009, Acta medica Scandinavica.

[2]  M. Allessie,et al.  Atrial fibrillation begets atrial fibrillation. A study in awake chronically instrumented goats. , 1995, Circulation.

[3]  B. Hockings,et al.  Intravenous flecainide versus amiodarone for recent-onset atrial fibrillation. , 1995, The American journal of cardiology.

[4]  A. Capucci,et al.  Conversion of recent-onset atrial fibrillation by a single oral loading dose of propafenone or flecainide. , 1994 .

[5]  A. Madrid,et al.  Comparison of flecainide and procainamide in cardioversion of atrial fibrillation. , 1993, European heart journal.

[6]  J. Kingma,et al.  Acute pharmacologic conversion of atrial fibrillation and flutter: the role of flecainide, propafenone, and verapamil. , 1992, The American journal of cardiology.

[7]  A. Capucci,et al.  Effectiveness of loading oral flecainide for converting recent-onset atrial fibrillation to sinus rhythm in patients without organic heart disease or with only systemic hypertension. , 1992, The American journal of cardiology.

[8]  H. Huikuri,et al.  Usefulness of a postoperative exercise test for predicting cardiac events after coronary artery bypass grafting. , 1992, The American journal of cardiology.

[9]  A L Waldo,et al.  Events in the cardiac arrhythmia suppression trial: baseline predictors of mortality in placebo-treated patients. , 1991, Journal of the American College of Cardiology.

[10]  H. Crijns,et al.  Prediction of uneventful cardioversion and maintenance of sinus rhythm from direct-current electrical cardioversion of chronic atrial fibrillation and flutter. , 1991, The American journal of cardiology.

[11]  H L Greene,et al.  Mortality and morbidity in patients receiving encainide, flecainide, or placebo. The Cardiac Arrhythmia Suppression Trial. , 1991, The New England journal of medicine.

[12]  J. Kingma,et al.  Intravenous flecainide versus verapamil for acute conversion of paroxysmal atrial fibrillation or flutter to sinus rhythm. , 1989, The American journal of cardiology.

[13]  I. V. Van Gelder,et al.  Acute conversion of atrial fibrillation to sinus rhythm: clinical efficacy of flecainide acetate. Comparison of two regimens. , 1988, European heart journal.

[14]  L A Moyé,et al.  The cardiac arrhythmia suppression trial. Casting suppression in a different light. , 1995, Circulation.

[15]  G. Botto,et al.  Conversion of recent-onset atrial fibrillation by a single oral loading dose of propafenone or flecainide. , 1994, The American journal of cardiology.