Efficacy of agents for pharmacologic conversion of atrial fibrillation and subsequent maintenance of sinus rhythm: a meta-analysis of clinical trials.
BACKGROUND
Physicians have little evidentiary guidance for pharmacologic agent selection for atrial fibrillation (AF).


OBJECTIVE
To assess antiarrhythmic agent efficacy for AF conversion and subsequent maintenance of sinus rhythm (MSR).


METHODS
We searched the clinical trial database of the Cochrane Collaboration and MEDLINE encompassing literature from 1948 to May 1998.


METHODS
We selected 36 (28%) articles eligible as randomized trials of nonpostoperative AF conversion or MSR in adults.


METHODS
Study quality; rates of conversion, MSR, and adverse events were extracted.


RESULTS
Compared with control treatment (placebo, verapamil, diltiazem, or digoxin), the odds ratio (OR) for conversion was greatest for ibutilide/dofetilide (OR=29.1; 95% confidence interval [CI], 9.8-86.1) and flecainide (OR=24.7; 95% CI, 9.0-68.3). Less strong but conclusive evidence existed for propafenone (OR=4.6; 95% CI, 2.6-8.2). Quinidine (OR=2.9; 95% CI, 1.2-7.0) had moderate evidence of efficacy for conversion. Disopyramide (OR=7.0; 95% CI, 0.3-153.0) and amiodarone (OR=5.7; 95% CI, 1.0-33.4) had suggestive evidence of efficacy. Sotalol (OR=0.4; 95% CI, 0.0-3.0) had suggestive evidence of negative efficacy. For MSR, strong evidence of efficacy existed for quinidine (OR=4.1; 95% CI, 2.5-6.7), disopyramide (OR=3.4; CI, 1.6-7.1), flecainide (OR=3.1; 95% CI, 1.5-6.2), propafenone (OR=3.7; 95% CI, 2.4-5.7), and sotalol (OR=7.1; 95% CI, 3.8-13.4). The only amiodarone data, from comparison with disopyramide, provided moderate evidence of efficacy for MSR. No trial evaluated procainamide. Direct agent comparisons and adverse event data were limited.


CONCLUSIONS
Although multiple antiarrhythmic agents had strong evidence of efficacy compared with control treatment for MSR, ibutilide/dofetilide and flecainide had particularly strong evidence of efficacy compared with control treatment for AF conversion. There is sparse and inconclusive evidence on direct agent comparisons and adverse event rates. Obtaining information regarding these relative efficacies should be a research priority.
Miller
M R
MR
Division of Pediatric Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. mmiller@ahrq.gov
McNamara
R L
RL
Segal
J B
JB
Kim
N
N
Robinson
K A
KA
Goodman
S N
SN
Powe
N R
NR
Bass
E B
EB
D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000188:drug therapy*; D019317:Evidence-Based Medicine; D006801:Humans; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic
D000889:Anti-Arrhythmia Agents