Atrial fibrillation: paroxysmal: amiodarone was more effective then verapamil at cardioversion.

Clinical bottom line (level 1b)

Patients with paroxysmal atrial fibrillation who received amiodarone compared with verapamil were more likely to revert acutely to sinus rhythm (NNT = 1 at 3 hours) .
There was no clear difference in adverse effects.

Noc et al: American Journal of Cardiology 1990; 65: 679-680

Expires November 2003

The study

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

24 patients (aged range 51 to 85 years; mean 71, 63% male) paroxysmal atrial fibrillation

Excluded if

known or suspected conduction disturbances, including pre-excitation

hyperthyroidism

sick sinus syndrome

concomitant therapy with antiarrhythmic drugs

arrhythmia-related systemic arterial hypotension

signs of heart failure

Control Group: (n = 11, 11 analysed): verapamil 0.075 mg/kg iv over 1 minute, repeated after 10 minutes
Experimental Group: (n = 13, 13 analysed): amiodarone 5mg/kg iv over 3 minutes

100% followed for 3 hours

The evidence

Outcome	Time to outcome	CER	EER	RRR (95% CI)	ARR (95% CI)	NNT (95% CI)
no sinus rhythm	3 hours	11 (100%)	3 (23.1%)	77% (38% to 91%)	76.9% (54.0% to 99.8%)	1 (1 to 2)
adverse effects	3 hours	1 (9.09%)	1 (7.69%)	15% (-1101% to 94%)	1.40% (-20.9% to 23.7%)	72 (NNT = 4 to infinity; NNH = 5 to infinity)

adverse effects: verapamil- slowing of ventricular response and decrease in arterial pressure; amiodarone- decrease in arterial pressure without bradycardia

Comments

Extremely short follow-up and the small numbers make this result much less certain.

Citation

Noc M, Stajer D, Horvat M: Intravenous amiodarone versus verapamil for acute conversion of paroxysmal atrial fibrillation to sinus rhythm. American Journal of Cardiology 1990; 65: 679-680

Contributor: Chris Ball and Clare Wotton, November 2000
Reviewer:

_{Clinical Question.}

_Patient	_AF
_{Intervention or Exposure}	_amiodarone
_Comparison	_verapamil
_Outcome	_{sinus rhythm}