Considerations for the success of topical amiodarone to prevent postoperative atrial fibrillation.

600 The Journ one in the perioperative period prevents postoperative AF; however, its challenging side-effect profile limits its routine and widespread use as prophylaxis. It was therefore with great interest that we recently read the report by Feng and colleagues describing their success in applying a topical amiodarone-releasing hydrogel on the atrial surface during coronary artery bypass grafting operations. Feng and colleagues randomly assigned 100 patients to receive either usual care or the addition of amiodarone 1 mg/kg mixed with Co-Seal (Baxter Healthcare, Deerfield, Ill) diffusely sprayed over the left and right atrial epicardium before sternal closure. Feng and colleagues reported a significant reduction in the incidence of postoperative AF with topical amiodarone (usual care vs amiodarone, 26% vs 8%; P< .01). In contrast to the challenges associated with systemic amiodarone, Feng and colleagues noted no safety concerns associated with the amiodarone-releasing hydrogel application. Feng and colleagues are to be congratulated for an elegant study, even if the study population was relatively small. Moreover, the design was limited by the absence of blinding, a clear randomization process, or a placebo therapy to serve as a control. Nevertheless, the results of the pilot study were striking, and after its publication we began to apply the therapy to all our subsequent cardiac surgical patients with no previous history of AF.We applied the therapy in a manner similar to that described by Feng and colleagues, except that we increased the dose to 150 mg for all patients (instead of 1 mg/kg). All patients were followed up with telemetry after surgery. Although we were enthusiastic at first, we ultimately were disappointed with our experience. The rate of AF among 100 consecutive patients who served as historical controls was not different from the rate of AF among the subsequent 50 patients who were treated with topical amiodarone