Atrial fibrillation: acute: iv flecainide led to faster but not more successful cardioversion than oral

Clinical bottom line (level 1b)

  1. Patients with acute atrial fibrillation who received oral flecainide compared with iv flecainide were not clearly less likely to be in sinus rhythm after 8 hours.
  2. Patients given iv flecainide cardioverted faster (by roughly 1 hour)
Alp et al: Heart 2000; 84 : 37-40
Expires November 2003

The study

Double-blinded concealed randomised trial with intention-to-treat
Setting: university hospital, UK

79 patients (aged ?, ?% male) with symptomatic acute atrial fibrillation (lasting < 48 hours and a ventricular rate > 100 beats/min)

Excluded if
  • current treatment with flecainide
  • permanent cardiac pacemaker
  • aged < 18
  • haemodynamic compromise requiring immediate cardioversion
  • congestive heart failure (NYHA class III or IV)
  • myocardial infarction within last 3 months
  • high grade ventricular arrhythmias
  • pregnancy
  • severe hepatic or renal failure

    Control Group: (n = 39, 39 analysed): flecainide iv 2 mg/kg (maximum 150 mg) in 100 ml 5% glucose over 30 min and placebo
    Experimental Group: (n = 40, 40 analysed): flecainide orally 4 mg/kg (maximum 300 mg) and placebo

    100% followed for 8 hours

    The evidence

    Outcome Time to outcome CER EER RRR
    (95% CI)    		 ARR
    (95% CI)    		 NN T
    (95% CI)
    reversion to sinus rhythm 8 hours 28
    (71.8%)    		 30
    (75.0%)    		 -4%
    (-36% to 20%)    		 -3.21%
    (-22.7% to 16.3%)    		 -31
    (NNT = 6 to infinity;
    NNH = 4 to infinity)

  • mean time to cardioversion: oral flecainide 110 min v. iv flecainide 52 min (p < 0.002)

    Comments

    1. No adverse effects were noted in either group.

    Citation

    1. Alp NJ, Bell JA, Shahi M: randomised double blind trial of oral versus intravenous flecainide for the cardioversion of acute atrial fibrillation. Heart 2000; 84 : 37-40
    Search Terms: from ACP Journal Club other articles noted
    Contributor: Chris Ball, November 2001
    Reviewer:

    Clinical Question.
    Patient acute atrial fibrillation
    Intervention or Exposure oral flecainide
    Comparison intravenous (iv) flecainide
    Outcome reversion to sinus rhythm
    		•