Atrial fibrillation: ibutilide before DC cardioversion increased initial success.

Clinical bottom line (level 1b)

  1. Patients with atrial fibrillation who were given ibutilide before transthoracic DC cardioversion, were more likely to have successful conversion to sinus rhythm than those not given ibutilide (NNT = 4 at minutes) .
  2. Ibutilide did not appear to affect long term outcome (6 months) (NNH = 10 at 6 months)
Oral et al: New England Journal of Medicine 1999; 340 (24): 1849-1854
Expires July 2003

The study

Unblinded ?concealed randomised trial ?with intention-to-treat
Setting: general hospital, USA

100 patients (aged mean 64 years, 73% male) referred for cardioversion for an episode of atrial fibrillation that had lasted more than six hours

Excluded if
  • <18 years old
  • pregnant
  • inadequate anticoagulation in those in whom atrial fibrillation had been present for >48 hours
  • corrected QT interval of >480 seconds, unless QT prolongation was attributable to amiodarone
  • unable or unwilling to provide consent
  • left ventricular ejection fraction <0.30


    • Control Group: (n = 50, 50 analysed): transthoracic cardioversion
    Experimental Group: (n = 50, 50 analysed): transthoracic cardioversion with ibutilide pretreatment, 1 mg transfused over 10 minutes

    100% followed for 6 months

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    successful conversion to sinus rhythm minutes 36
    (72.0%)    		 50
    (100%)    		 -39.0%
    (-65.0% to -17.0%)    		 -28.0%
    (-40.5% to -15.6%)    		 4
    (2 to 6)
    reversion to AF 6 months 29
    (57%)    		 34
    (67%)    		 -17%
    (-59% to 14%)    		 -10%
    (-28% to 8.8%)    		 -10
    (NNT = 3 to infinity;
    NNH = 11 to infinity)

    Citation

    1. Oral H, Souza JJ, Michaud GF, et al: Facilitating transthoracic cardioversion of atrial fibrillation with ibutilide pretreatment. New England Journal of Medicine 1999; 340 (24): 1849-1854
    Contributor: Clare Wotton and Bob Phillips, January 2000
    Reviewer:

    Clinical Question.
    Patient atrial fibrillation
    Intervention or Exposure transthoracic cardioversion with ibutilide
    Comparison without ibutilide
    Outcome conversion to sinus rhythm