Intravenous plus oral amiodarone, atrial septal pacing, or both strategies to prevent post-cardiothoracic surgery atrial fibrillation: the Atrial Fibrillation Suppression Trial II (AFIST II).
BACKGROUND
The effect of a hybrid intravenous and oral prophylactic amiodarone regimen on postcardiothoracic surgery (CTS) atrial fibrillation (AF) is unknown. The impact of active atrial septal pacing on post-CTS AF has not been well characterized. In addition, the effect of using both amiodarone and atrial septal pacing together to prevent atrial fibrillation is unknown.


RESULTS
Patients (n=160) were randomized to amiodarone or placebo and then to pacing or no pacing using a 2x2 factorial design. All therapies began within 6 hours post-CTS. Amiodarone was given by intravenous infusion for the first 24 hours (1050 mg total) followed by oral therapy for 4 postoperative days (4800 mg total). Atrial septal pacing was given for 96 hours. Amiodarone reduced the risk of AF by 43% and the risk of symptomatic AF by 68% (P=0.037 and P=0.019) versus placebo. Atrial septal pacing did not reduce AF or symptomatic AF incidence versus no pacing. The risk of post-CTS AF in the patients receiving amiodarone+pacing was lower than the placebo+no pacing and the placebo+pacing groups (57.9% and 60.5% reductions, P=0.047 and P=0.040, respectively).


CONCLUSIONS
Amiodarone given as both an intravenous and oral regimen is effective at reducing post-CTS AF but atrial septal pacing is ineffective. Combining amiodarone and pacing is better than placebo with or without pacing but not amiodarone alone.
White
C Michael
CM
Division of Cardiology, Drug Information, and Cardiac Surgery at Hartford Hospital, Hartford, CT 06102-5037, USA.
Caron
Michael F
MF
Kalus
James S
JS
Rose
Heidi
H
Song
Jessica
J
Reddy
Prabashni
P
Gallagher
Robert
R
Kluger
Jeffrey
J
D000284:Administration, Oral; D000368:Aged; D000638:Amiodarone / Q000008:administration & dosage / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000191:economics / Q000517:prevention & control*; D002304:Cardiac Pacing, Artificial; D003131:Combined Modality Therapy; D001026:Coronary Artery Bypass; D023381:Endpoint Determination; D005260:Female; D006325:Heart Atria; D006346:Heart Septum; D019918:Heart Valve Prosthesis Implantation; D017721:Hospital Costs; D006801:Humans; D007262:Infusions, Intravenous; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D019616:Thoracic Surgical Procedures
D000638:Amiodarone