Atrial fibrillation: acute: cardioversion: flecainide combined with digoxin was more effective than digoxin alone.

Clinical bottom line (level 1b)

  1. Patients with recent-onset AF were more likely to convert to sinus rhythm on flecainide and digoxin compared with digoxin alone (NNT = 3 at 6 hours) .
  2. Adverse effects were more common with flecainide (NNH = 6 at 6 hours) .
Donovan et al: American Journal of Cardiology 1991; 67: 137-141
Expires November 2003

The study

Double-blinded concealed randomised trial without intention-to-treat
Setting: acute hospital, Australia

104 patients (aged range 21 to 90 years; mean 60, 71% male) recent-onset AF (> or = 30 minutes and < or = 72 hours with ventricular response > or = 120 bpm)

Excluded if
  • <18 years old
  • K > 5.5 mmol/l or < 3.5 mmol/l
  • severe heart failure
  • severe circulatory failure requiring inotropes
  • pacemaker, sick sinus syndrome, high-degree AV block
  • recent antiarrhythmic therapy (including amiodarone within 3 months)
  • digitalis intoxication
  • flecainide hypersensitivity
  • pregnancy and lactation


    • Control Group: (n = 52, 51 analysed): placebo
    Experimental Group: (n = 52, 51 analysed): flecainide 2mg/kg iv over 30 minutes: max dose 150 mg
    All patients not currently on digoxin received iv digoxin 500 µ g over 30 minutes.
    98% followed for 6 hours
    Outcome notes:
    • adverse effects : hypotension, arrhythmias, hot flushes

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    no conversion to sinus rhythm 6 hours 33
    (64.7%)    		 17
    (33.3%)    		 48%
    (20% to 67%)    		 31.4%
    (13.0% to 49.8%)    		 3
    (2 to 8)
    adverse effects 6 hours 3
    (5.88%)    		 11
    (21.6%)    		 -267%
    (-1137% to -9%)    		 -15.7%
    (-28.7% to -2.68%)    		 -6
    (-37 to -3)

    Comments

    1. Very short follow-up. Many patients spontaneously cardiovert within 24 hours.
    2. Unclear how many patients revert to AF or the long-term effect on mortality or strokes.

    Citation

    1. Donovan KD, Dobb GJ, Coombs LJ, et al: Reversion of recent-onset atrial fibrillation to sinus rhythm by intravenous flecainide. American Journal of Cardiology 1991; 67: 137-141
    Search Terms: atrial fibril* in Cochrane
    Contributor: Chris Ball and Clare Wotton, November 2000
    Reviewer:

    Clinical Question.
    Patient AF
    Intervention or Exposure flecainide
    Comparison placebo
    Outcome sinus rhythm, side effects