Repeated Amiodarone Dosing In Cardiac surgicaL Procedures

Repeated Amiodarone Dosing In Cardiac surgicaL Procedures

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).

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.

Inclusion Criteria:

• Subject must be 18 years old or older
• Subject must be willing to give written informed consent
• Subject must undergo or scheduled for non-emergent cardiac surgery, including coronary artery bypass grafting (CABG), non-infectious valve repair or replacement, atrial or septal defect repair, thoracic aortic replacement surgery, or any combination of these procedures

Exclusion Criteria:

• Documented allergy to amiodarone or iodine
• History of atrial fibrillation or other heart conduction system abnormality
• History of cardiac maze, pulmonary vein isolation, or other procedure affecting the conduction system
• Scheduled cardiac maze, pulmonary vein isolation, or other procedure affecting the conduction system
• Low cardiac index or cardiogenic shock requiring pharmacologic or mechanical support
• History of pre-existing respiratory system disease requiring oxygen therapy prior to admission
• History of cirrhosis or other chronic liver diseases
• Pregnancy or breastfeeding mothers
• Prisoner status