Atrial fibrillation: acute: flecainide helped cardioversion, but could cause hypotension.

Clinical bottom line (level 1b)

  1. Patients with recent onset atrial fibrillation who received flecainide in addition to digoxin were more likely to revert to sinus rhythm than those who did not (NNT = 3 at 6 hours) .
  2. Patients were more likely to develop severe hypotension on flecainide (NNH = 6 at 6 hours) .
Donovan et al: American Journal of Cardiology 1992; 70: 50A-55A
Expires November 2004

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, 69% male) recent-onset atrial fibrillation

Excluded if
  • aged < 18
  • AF for < 30 minutes, >72 hours
  • severe heart or circulatory failure
  • sick sinus syndrome, high degree AV block, bifascicular block or pacemaker
  • recent antiarrhythmic drug (within 5 half-lives)
  • potassium >5.5 or < 3.5 mmol/l
  • digoxin toxicity
  • flecainide hypersensitivity


    • Note:
  • All patients not already on digoxin, received digoxin 500 µ g over 30 minutes


    • Control Group: (n = 52, 51 analysed): placebo
    Experimental Group: (n = 52, 51 analysed): flecainide 2 mg/kg iv over 30 minutes, maximum dose 150 mg

    100% followed for 6 hours

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    no reversion to sinus rhythm 60 minutes 44
    (86.3%)    		 22
    (43.1%)    		 50%
    (30% to 64%)    		 43.1%
    (26.6% to 59.7%)    		 2
    (2 to 4)
    no reversion 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)
    severe hypotension 6 hours 3
    (5.88%)    		 11
    (21.6%)    		 -267%
    (-1137% to -9%)    		 -15.7%
    (-28.7% to -2.68%)    		 -6
    (-37 to -3)

    Citation

    1. Donovan KD, Dobb GJ, Coombs LJ, et al: Efficacy of flecainide for the reversion of acute onset atrial fibrillation. American Journal of Cardiology 1992; 70: 50A-55A
    Contributor: Chris Ball and Clare Wotton, November 2000
    Reviewer:

    Clinical Question.
    Patient atrial fibrillation
    Intervention or Exposure flecainide
    Comparison placebo
    Outcome reversion to sinus rhythm, adverse effects