This study will screen and consent approximately 150 patients undergoing non-emergent cardiac surgery. Approximately 60 of these patients are likely to develop stable postoperative atrial fibrillation (POAF) in the postoperative period. Amiodarone is commonly given as an initial intravenous (IV) bolus (150 mg IV) followed by a combined IV and oral load to a total dose of 8 gm. Because of amiodarone's beta-blocker activity, the IV bolus in patients with POAF is associated with a reduced heart rate that may lead to restoration of NSR. For this reason, some clinicians will provide up to 5 additional IV amiodarone boluses during the drug's loading period to treat RVR.
This study is a single-center, prospective, randomized, open-label trial of subjects who develop atrial fibrillation after non-emergent cardiac surgery at the University of Kentucky Chandler Medical Center (UKCMC). Patients will be randomized to receive either a conventional amiodarone dosing regimen (CDR) or a repeated amiodarone bolus dosing regimen (RBDR).