Pragmatic Amiodarone Trial to Reduce Postoperative Atrial Fibrillation in Patients Undergoing Cardiac Surgery

Postoperative atrial fibrillation is quite common after cardiac surgery with up to 1 in 3 patients experiencing this abnormal heart rhythm. Amiodarone, a medication commonly used to treat atrial fibrillation, has been previously shown to be an effective prophylactic agent at decreasing the occurrence of postoperative atrial fibrillation in patients who underwent coronary artery bypass surgery. However, despite many studies which have demonstrated its effectiveness, it has not been widely used due to the concern of side effects that can occur such as slow heart rate, low blood pressure, and lung toxicity. We have designed a study to test the effectiveness and safety of a short course of postoperative prophylactic amiodarone for patients undergoing non-coronary artery bypass cardiac surgery. We hypothesize that patients who receive the prophylactic amiodarone will have decreased rates of postoperative atrial fibrillation without significantly increased side effects compared to patients who receive the standard postoperative care after non-coronary artery bypass cardiac surgery.

Inclusion Criteria: * \>= 18 years of age * All genders * All non-coronary artery bypass cardiac surgery patients * Preoperative normal sinus rhythm Exclusion Criteria: * Pre-existing atrial fibrillation or atrial arrhythmias * Pre-existing heart block * Cardiogenic shock * Sick sinus syndrome * Marked sinus bradycardia * Preoperative amiodarone use * Contraindication to amiodarone use * PR interval \> 240 ms * QTc \> 550 ms * 2nd or 3rd degree heart block * Liver impairment (INR \> 1.7, AST/ALT \> 2x normal) * Uncontrolled hyperthyroidism or hypothyroidism * Interstitial lung disease * Pregnancy and/or breastfeeding * Known hypersensitivity to any components of amiodarone, including iodine * Emergent operation * Planned MAZE or Pulmonary Vein Isolation procedure