Diltiazem versus Amiodarone for New-Onset Atrial Arrhythmias in Non-Cardiac Post Surgical Patients: A Cohort Study

Objective: To evaluate safety and efficacy of diltiazem versus amiodarone for conversion of atrial arrhythmias in non-cardiac post-surgical critically ill patients.
Design: A cohort study of non-cardiac post surgical patients admitted to the surgical intensive care unit with new-onset atrial tachyarrhythmias which were treated by protocol. In the first year patients were treated with diltiazem, and amiodarone was used in
the second year.
Setting: Thirty-eight bed surgical intensive care unit in a university medical center. Patients and participants: Sixty-one patients were treated for new-onset atrial tachyarrhythmias: 31
received diltiazem and 30 received amiodarone.
Interventions: Diltiazem loading dose 0.25 mg/kg and continuous infusion or amiodarone 150 mg loading dose and continuous infusion.
Measurements and results: Both groups had comparable demographics. Neither 24-hour conversion rates (diltiazem 87.1%, amiodarone
86.7%, p =0.96) nor mean times (±Standard Deviation) to conversion were statistically different (diltiazem 6.9±6.3 hours versus amiodarone 5.0±4.2 hours, p =0.52). Three patients developed hypotension (diltiazem 1, amiodarone 2, p =0.57).
Conclusions: Amiodarone and diltiazem led to no differences for treating atrial tachyarrhythmias in non-cardiac surgical patients based on safety and efficacy. Randomized controlled studies are
needed to compare diltiazem versus amiodarone for conversion of postoperative atrial fibrillation.