Atrial fibrillation: ibutilide was more effective than sotalol at cardioversion.

Clinical bottom line (level 1b)

  1. Patients with recent-onset atrial fibrillation or flutter who took ibutilide compared with sotalol were more likely to revert to sinus rhythm: atrial flutter (NNT = 2 at 60 minutes) ; atrial fibrillation (NNT = 5 at 60 minutes) .
Vos et al: Heart 1998; 79: 568-575
Expires November 2003

The study

Double-blinded concealed randomised trial with intention-to-treat
Setting: 43 acute hospitals, Europe

308 patients (aged range 21 to 89 years; mean 60, 72% male) recent-onset atrial fibrillation or flutter (duration for 3 to 45 days)

Excluded if
  • aged < 18
  • haemodynamically unstable (systolic bp < 90 mmHg, diastolic bp > 105 mmHg)
  • potassium < 4.0 mmol/l
  • ventricular rate < 60 beats/min
  • QTc > 440 ms
  • hyperthyroidism
  • bronchospastic disease
  • unstable angina, myocardial infarction or cardiac surgery within previous 30 days
  • known sinus node dysfunction, 2nd or 3rd degree AV block, bundle-branch block, Wolff-Parkinson-While syndrome, torsade de pointes


    • Control Group: (n = 103, 103 analysed): sotalol 1.5 mg/kg
    Experimental Group: (n = 205, 205 analysed): ibutilide 1mg or 2mg iv over 10 minutes

    100% followed for 60 minutes

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    no termination of atrial flutter 60 minutes 17
    (81.0%)    		 13
    (36.1%)    		 55%
    (28% to 72%)    		 44.8%
    (21.9% to 67.8%)    		 2
    (1 to 5)
    no termination of atrial fibrillation 60 minutes 73
    (89.0%)    		 116
    (68.6%)    		 23%
    (12% to 32%)    		 20.4%
    (10.7% to 30.1%)    		 5
    (3 to 9)

  • 21 patients with atrial flutter were in the control group and 36 were in the ibutilide group. 82 patients with atrial fibrillation were in the control group, compared with 169 in the ibutilide group.
  • The higher dose of ibutilide tended to be more effective.
  • There was no clear difference between the groups for proarrhythmic activity.

    • Citation

    1. Vos MA, Golitsyn SR, Stangl K, et al: Superiority of ibutilide (a new class III agent) over DL-sotalol in converting atrial flutter and atrial fibrillation. Heart 1998; 79: 568-575
    Contributor: Chris Ball and Clare Wotton, November 2000
    Reviewer:

    Clinical Question.
    Patient AF or flutter
    Intervention or Exposure ibutilide
    Comparison sotalol
    Outcome termination of flutter or fibrillation