Tachycardia: verapamil had no clear effect on conversion to sinus rhythm.

Clinical bottom line (level 1b-)

  1. Patients with atrial fibrillation who were given verapamil, had no clear difference in conversion to sinus rhythm than those given placebo.
  2. Patients with atrial flutter who were given verapamil, had no clear difference in conversion to sinus rhythm than those given placebo.
Aronow and Ferlinz: Clinical and Investigative Medicine 1980; 3: 35-39
Expires October 2003

The study

Double-blinded ?concealed randomised cross-over trial with intention-to-treat
Setting: university hospital, USA

28 patients (aged range 37 to 70 years, 100% male) atrial fibrillation or atrial flutter
Note:
  • 10 patients had chronic obstructive pulmonary disease.


    • Control Group: (n = 18, 18 analysed): normal saline injected intravenously
    Experimental Group: (n = 27, 27 analysed): verapamil 0.075 mg/kg to a maximum dose of 5.0 mg, injected intravenously over a 1 minute period
    If within 10 minutes after the first drug was given, the ventricular rate did not slow by > or = 15% or it remained > or = 100 beats/min, the patient received the other drug. If the ventricular rate did not alter sufficiently after the second drug, verapamil 0.15 mg/kg (maximum dose 10.0 mg) was injected intravenously over a 1 minute period.
    0% followed for ? weeks

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    conversion to sinus rhythm from atrial fibrillation (n=14 in placebo group; n=20 in verapamil group) unknown 0
    (0.00%)    		 3
    (15.0%)    		 -100%
    (% to %)    		 -15.0%
    (-30.7% to 0.65%)    		 7
    (NNT = 3 to infinity;
    NNH = 154 to infinity)
    conversion to sinus rhythm from atrial flutter (n=4 in placebo group; n=7 in verapamil group) unknown 0
    (0.00%)    		 1
    (14.3%)    		 -100%
    (% to %)    		 -14.3%
    (-40.2% to 11.6%)    		 7
    (NNT = 2 to infinity;
    NNH = 9 to infinity)

    Comments

    1. The trial is too small to show any clear difference in conversion to sinus rhythm between the two treatments.
    2. Not all of the patients were crossed over to the second treatment drug.

    Citation

    1. Aronow WS, and Ferlinz J: Verapamil versus placebo in atrial fibrillation and atrial flutter.. Clinical and Investigative Medicine 1980; 3: 35-39
    Contributor: Clare Wotton and Bob Phillips, October 1999
    Reviewer:

    Clinical Question.
    Patient atrial fibrillation or flutter
    Intervention or Exposure verapamil
    Comparison placebo
    Outcome conversion to sinus rhythm