Single-day loading dose of oral amiodarone for the prevention of new-onset atrial fibrillation after coronary artery bypass surgery.
BACKGROUND
Various regimens have been proposed for the prevention of postoperative atrial fibrillation, including the use of intravenous and oral amiodarone. The purpose of this study was to determine the effectiveness of a single-day loading dose of oral amiodarone in prophylaxis of atrial fibrillation during the 7 days after coronary artery bypass surgery.


METHODS
We conducted a double-blind, randomized, placebo-controlled study encompassing 315 consecutive patients who underwent coronary artery bypass surgery. They received either amiodarone (159 patients) or placebo (156 patients). Therapy consisted of a single oral loading dose of 1200 mg of amiodarone 1 day before surgery, followed by the maintenance dose of 200 mg daily during the next 7 days. Only episodes of atrial fibrillation lasting more than 1 hour or associated with hemodynamic compromise were taken into consideration.


RESULTS
Overall, the incidence of atrial fibrillation was similar in patients who received amiodarone (31/159, 19.5%) and placebo (33/156, 21.2%) (P = .78). However, amiodarone reduced the incidence of atrial fibrillation in elderly patients (age > or = 60 years): it occurred in 20 of 75 (26.7%) patients on amiodarone and in 28 of 65 (43.1%) patients in the placebo group (P = .05). There were no differences between the study groups regarding the postoperative intrahospital morbidity and mortality and the duration of hospital stay.


CONCLUSIONS
A single-day loading dose of oral amiodarone (1200 mg) does not prevent postoperative atrial fibrillation in a general population of patients undergoing coronary artery bypass surgery. However, it appears that this regimen reduces the occurrence of postoperative atrial fibrillation in elderly patients.
Maras
D
D
Department of Cardiology, the "Dr Aleksandar D. Popović "Cardiovascular Research Center, the Department of Cardiac Surgery, Dedinje Cardiovascular Institute, Belgrade, Yugoslavia.
Bosković
S D
SD
Popović
Z
Z
Nesković
A N
AN
Kovacević
S
S
Otasević
P
P
Marinković
J
J
Vuk
L
L
Borzanović
M
M
Nastasić
S
S
Jovanović
T
T
Bojić
M
M
Babić
R
R
Popović
A D
AD
D000284:Administration, Oral; D000638:Amiodarone / Q000008:administration & dosage*; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage*; D001281:Atrial Fibrillation / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D003327:Coronary Disease / Q000601:surgery; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D007902:Length of Stay; D008875:Middle Aged
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone