Atrial fibrillation: chronic: sotalol was less effective than quinidine for cardioversion.

Clinical bottom line (level 1b)

  1. Patients with symptomatic chronic atrial fibrillation who took sotalol compared with quinidine were less likely to revert to sinus rhythm (NNH = 3 at 7 days) .
  2. There was no clear difference in the number of patients who remained in sinus rhythm at 6 months or who experienced side-effects.
Hohnloser et al: Journal of the American College of Cardiology 1995; 26 (4): 852-858
Expires November 2003

The study

Unblinded ?concealed randomised trial with intention-to-treat
Setting: university hospital, Germany

50 patients (aged mean 62 years, 64% female) ECG-proven persistent atrial fibrillation (for > 48 hours, < 6 months) and associated symptoms (palpitations, dyspnoea, chest pain, light-headedness)

Excluded if
  • aged < 18, > 80
  • acute MI within 4 weeks; unstable angina
  • congestive heart failure (NYHA class IV)
  • uncorrected electrolyte imbalance: K < 4.0 mmol/l or Mg < 1.5 mmol/l
  • hepatic insufficiency
  • hyperthyroidism
  • previous treatment with sotalol or quinidine; concomitant therapy with other class I to IV agents


    • Control Group: (n = 25, 25 analysed): quinidine 200 mg test dose po, then 500 mg bd for 3 days. If still ineffective patients had 250 mg bd and verapamil 80 mg qds.
    Experimental Group: (n = 25, 25 analysed): sotalol 80 mg bd po for 1 day, then increased to 160 mg bd for 6 days

    100% followed for 6 months

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    failure to convert to sinus rhythm 7 days 10
    (40.0%)    		 20
    (80.0%)    		 -100%
    (-236% to -19%)    		 -40.0%
    (-64.8% to -15.2%)    		 -3
    (-7 to -2)
    no sinus rhythm 6 months 7
    (28.0%)    		 11
    (44.0%)    		 -57%
    (-239% to 27%)    		 -16.0%
    (-42.2% to 10.2%)    		 -6
    (NNT = 2 to infinity;
    NNH = 10 to infinity)
    side effects 6 months 14
    (56.0%)    		 11
    (44.0%)    		 21%
    (-38% to 55%)    		 12.0%
    (-15.5% to 39.5%)    		 8
    (NNT = 6 to infinity;
    NNH = 3 to infinity)

    Comments

    1. The study is too small to show any difference in effect on patients remaining in sinus rhythm at six months.
    2. Other studies have shown that quinidine increases mortality.

    Citation

    1. Hohnloser SH, van de Loo A, Baedeker F: Efficacy and proarrhythmic hazards of pharmacologic cardioversion of atrial fibrillation: prospective comparison of sotalol versus quinidine. Journal of the American College of Cardiology 1995; 26 (4): 852-858
    Search Terms: atrial fibril* in Cochrane
    Contributor: Chris Ball and Clare Wotton, November 2000
    Reviewer:

    Clinical Question.
    Patient AF
    Intervention or Exposure sotalol
    Comparison quinidine
    Outcome sinus rhythm