Intravenous amiodarone for the prevention of atrial fibrillation after open heart surgery: the amiodarone reduction in coronary heart (ARCH) trial

OBJECTIVES: This study was designed to test whether intravenous (i.v.) amiodarone would prevent atrial fibrillation and decrease hospital stay after open heart surgery. BACKGROUND: Atrial fibrillation commonly occurs after open heart procedures and is thought to be a significant determinant for prolongation of hospitalization. Oral amiodarone given preoperatively appears to reduce the incidence of atrial fibrillation. This study was designed to test whether the more rapid-acting i.v. formulation of amiodarone given postoperatively would reduce the incidence of atrial fibrillation. METHODS: Three hundred patients undergoing standard open heart surgery were randomized in a double-blind fashion to i.v. amiodarone (1 g/day for 2 days) versus placebo immediately after open heart surgery. The primary end points of the trial were incidence of atrial fibrillation and length of hospital stay. Baseline clinical variables and mortality and morbidity data were collected. RESULTS: Atrial fibrillation occurred in 67/142 (47%) patients on placebo versus 56/158 (35%) on amiodarone (p = 0.01). Length of hospital stay for the placebo group was 8.2 +/- 6.2 days, and 7.6 +/- 5.9 days for the amiodarone group (p = 0.34). No differences were noted in baseline variables, morbidity or mortality. CONCLUSIONS: Low-dose i.v. amiodarone was safe and effective in reducing the incidence of atrial fibrillation after heart surgery, but did not significantly alter length of hospital stay.