Efficacy of Amiodarone Versus Amiodarone and Dexmedetomidine on Heart Rate and Rhythm Following Aortic Cross-Clamp Opening During Cardiopulmonary Bypass and the Early Postoperative Period in Patients Undergoing Valve Replacement Surgery With Rheumati

Background: Long-standing atrial fibrillation (AF) is a common arrhythmia, often associated with rheumatic valvular disease, particularly mitral valve disease, which results in left atrial enlargement. In developing nations such as India, AF is found almost exclusively in association with rheumatic mitral stenosis and mitral regurgitation. Objective: To assess the effectiveness of amiodarone and dexmedetomidine in the treatment of atrial fibrillation after cardiac surgery, especially in patients undergoing cardiopulmonary bypass (CPB). Methods: The study compared the effects of amiodarone, an antiarrhythmic drug classified as a class III agent, with those of dexmedetomidine, a selective α2-adrenergic agonist, on rate control and recovery of normal sinus rhythm (NSR) after cardiac surgery. Their pharmacological effects, including adrenergic stimulation inhibition, modulation of sodium, potassium, and calcium channels, and anti-inflammatory effects, were experimented upon in the treatment of postoperative AF. Results: Amiodarone exhibited a high rate of conversion and maintenance of NSR in 50–70% of patients with minimal hemodynamic instability. The combination of amiodarone and dexmedetomidine had an additive effect that improved postoperative AF control and prevented hemodynamic fluctuations. Conclusion: Both amiodarone and dexmedetomidine are useful in the treatment of postoperative AF; amiodarone is better at controlling rhythm, while dexmedetomidine is better at controlling inflammation and hemodynamic stability.