Atrial fibrillation: chronic: internal electrode position had no effect on success of cardioversion.

Clinical bottom line (level 1b-)

  1. Electrode position had no clear effect on the success of internal cardioversion in patients with chronic atrial fibrillation.
Alt et al: American Journal of Cardiology 1997; 79: 621-625
Expires November 2004

The study

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

80 patients (aged mean 59 years, 80% male) chronic atrial fibrillation = 14 days documented on serial ECG

Excluded if
  • evidence of digitalis toxicity
  • electrolyte imbalance
  • hyperthyroidism
  • history of long QT syndrome
  • acute MI or cardiopulmonary operation within previous 6 weeks
  • history of thromboembolism
  • aged <21 or >75


    • Note:
  • All patients were anticoagulated with warfarin for = 2 weeks (adjusted so INR 2.5 to 4.2), and had any antiarrhythmic medication withheld for 5 half-lives before cardioversion.


    • Control Group: (n = 38, 38 analysed): internal cardioversion via defibrillation electrodes placed in the right atrium and coronary sinus. Catheter inserted in the right internal jugular vein
    Experimental Group: (n = 42, 42 analysed): internal cardioversion via defibrillation electrodes placed in the right atrium and left pulmonary artery. Catheter inserted in the femoral vein
    Shocks started at 60 V and increased at 40 V intervals until cardioversion was achieved. All patients received sotalol ( = 80 mg bd) after reversion to sinus rhythm, and continued anticoagulation for at least 4 weeks.
    100% followed for 12 months

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    no sinus rhythm minutes 3
    (7.89%)    		 3
    (7.14%)    		 10%
    (-322% to 81%)    		 0.75%
    (-10.8% to 12.3%)    		 130
    (NNT = 8 to infinity;
    NNH = 9 to infinity)
    no sinus rhythm 12 months 19
    (50.0%)    		 22
    (52.4%)    		 -5%
    (-61% to 32%)    		 -2.38%
    (-24.3% to 19.6%)    		 -42
    (NNT = 5 to infinity;
    NNH = 4 to infinity)

    Citation

    1. Alt E, Schmitt C, Ammer R, et al: Impact of electrode position on outcome of low-energy intracardiac cardioversion of atrial fibrillation. American Journal of Cardiology 1997; 79: 621-625
    Contributor: Chris Ball and Clare Wotton, November 2000
    Reviewer:

    Clinical Question.
    Patient chronic atrial fibrillation
    Intervention or Exposure pulmonary artery cardioversion
    Comparison coronary sinus cardioversion
    Outcome sinus rhythm