Atrial fibrillation: DC cardioversion was more successful in younger patients with atrial flutter.

Clinical bottom line (level 1b)

  1. Patients with the following prognostic factors were more likely to have successful cardioversion:
    • short duration of arrhythmia
    • atrial flutter
    • younger age
  2. Patients with the following prognostic factors were more likely to remain in sinus rhythm following cardioversion:
    • atrial flutter
    • heart failure: low NYHA functional class
    • non-rheumatic mitral valve heart disease
Van Gelder et al: American Journal of Cardiology 1991; 68: 41-46
Expires November 2004

The study

Prospective cohort study with objective outcomes, adjusted for confounding factors, not validated in an independent set of patients.

Setting: acute hospital, Holland

246 patients (aged range 25 to 86 years; mean 60, 56% male) chronic atrial fibrillation or flutter (for > 24 hours) referred for DC cardioversion

Excluded if
  • in sinus rhythm
  • unstable heart failure or cardiogenic shock
  • severe symtematic disease
  • sick sinus syndrome without pacemaker
  • recent acute MI
  • contraindications to anticoagulation therapy
  • if potassium < 3.5 mmol/l, INR > 4.8


    • All patients were anticoagulated for 4 weeks before cardioversion and received an antiarrhythmic (quinidine, flecainide, disopyramide, sotalol and amiodarone) if they complained of recurrent symptomatic arrhythmia.

    Logistic regression analysis performed on prognostic factors.

    100% followed for up to 3 years (mean 9 months)
    Outcomes studied:
  • cardioversion with AF
  • cardioversion with atrial flutter
  • in sinus rhythm

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    cardioversion with AF up to 3 years (mean 9 months) / 70%
    (62% to 78%)
    cardioversion with atrial flutter up to 3 years (mean 9 months) / 96%
    (91% to 100%)
    in sinus rhythm up to 3 years (mean 9 months) / 36%
    (30% to 42%)

    • factors predicting successful cardioversion:
      • short duration of last episode of arrhythmia
      • atrial flutter
      • age
    • factors predicting remaining in sinus rhythm:
      • atrial flutter
      • low NYHA functional class
      • non-rheumatic mitral valve heart disease
    • Left atrial size found not to be significant in this analysis.

    Comments

    1. No information on odds ratios given.

    Citation

    1. Van Gelder IC, Crijns HJ, Van Gilst WH, et al: Prediction of uneventful cardioversion and maintenance of sinus rhythm from direct-current electrical cardioversion of chronic atrial fibrillation and flutter. American Journal of Cardiology 1991; 68: 41-46
    Contributor: Nick Shenker and Chris Ball, November 2000
    Reviewer:

    Clinical Question.
    Patient AF
    Intervention or Exposure risk factors
    Outcome cardioversion