Atrial fibrillation: paroxysmal: no clear benefit from digoxin

Clinical bottom line (level 1b-)

  1. Patients with paroxysmal atrial fibrillation who took digoxin compared with placebo were not clearly less likely to have recurrent symptomatic episodes.
Murgatroyd et al: Circulation 1999; 99: 2765-2770
Expires November 2003

The study

Double-blinded ?concealed randomised cross-over trial without intention-to-treat
Setting: 9 acute hospitals, UK

43 patients (aged mean 58, 56% male) documented atrial fibrillation and symptomatic self-terminating episodes more than once a month

Excluded if
  • implanted cardiac pacemaker
  • hypertrophic cardiomyopathy
  • women who were pregnant, lactating or of childbearing potential and not using contraception
  • amiodarone or investigational drugs in previous 3 months
  • abnormal thyroid function
  • renal, hepatic, pulmonary or cardiac insufficiency or valvular heart disease that might cause progression to permanent AF
  • left atrial diameter > 45 mm
  • myocardial infarction, unstable angina, or cardiac revascularisation in within 3 months
  • known of suspected atrioventricular accessory pathway; history of second- or third-degree atrioventricular block or sinus node dysfunction
  • history of AF requiring cardioversion on >1 occasion
  • history of thromboembolism or symptoms such as syncope or angina judged by their physician to be due to atrial fibrillation
  • aged < 18
  • uncorrected electrolyte imbalance
  • serum potassium < 3.8 mmol/l


    • Note:
  • Patients were taken off antiarrhythmic medication for at least 5 half-lives before randomization.


    • Control Group: (n = 43, 43 analysed): placebo
    Experimental Group: (n = 43, 43 analysed): digoxin 125 µ g daily; adjusted so serum digoxin levels were 1.0 to 2.6 nmol/l

    100% followed for 2 months
    Outcome notes:
    • 2 episodes of symptomatic AF : recorded using event recorders

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    2 episodes of symptomatic AF 2 months 36
    (83.7%)    		 32
    (74.4%)    		 11%
    (-11% to 29%)    		 9.30%
    (-7.78% to 26.4%)    		 11
    (NNT = 4 to infinity;
    NNH = 13 to infinity)

    Comments

    1. The study is too small to show any differences between the two groups.
    2. Patients were randomised in blocks of four.

    Citation

    1. Murgatroyd FD, Gibson SM, Baiyan X, et al: Double-blind placebo-controlled trial of digoxin in symptomatic paroxysmal atrial fibrillation (CRAFT). Circulation 1999; 99: 2765-2770
    Search Terms: ?
    Contributor: Chris Ball and Clare Wotton, November 1999
    Reviewer:

    Clinical Question.
    Patient symptomatic paroxysmal atrial fibrillation
    Intervention or Exposure digoxin
    Comparison placebo
    Outcome symptomatic atrial fibrillation