Amiodarone prevents symptomatic atrial fibrillation and reduces the risk of cerebrovascular accidents and ventricular tachycardia after open heart surgery: results of the Atrial Fibrillation Suppression Trial (AFIST)

Abstract

Background: Atrial fibrillation (AF) is a common complication after cardiothoracic surgery (CTS). The role of amiodarone added to beta blocker as a preventive strategy in elderly patients undergoing CTS is not known. The Atrial Fibrillation Suppression Trial (AFIST) was a double blind, placebo-controlled trial that evaluated the efficacy of oral amiodarone in patients 60 years or older undergoing CTS. Beta blockers were administered as part of a critical pathway.

Methods: Elderly patients (n = 220, mean age 72 +/- 6.7 years) received amiodarone (n = 120) or placebo (n = 100). Patients enrolled less than 5 days before CTS received 6 g of drug over 6 days beginning on the day prior to OHS. Patients enrolled 5 days before CTS received 7 g of study drug over 9-10 days, starting on preoperative day 4 or 5.

Results: Amiodarone treated patients had a lower incidence of AF (22.5% vs. 38%, p = 0.01), symptomatic AF (4.2% vs. 18%, p = 0.001), cerebral vascular accident (1.7 vs. 7.0%, p = 0.04), and ventricular tachycardia (1.7% vs. 7.0%, p = 0.04) vs. placebo. Beta blocker use (87.5% vs. 91.0% ), nausea (26.7% vs. 16%, p = 0.056), symptomatic bradycardia (7.5% vs. 7%, p = 0.89), hypotension (14.2% vs. 10.0%) and 30 day mortality (3.3 vs. 4.0%, p = 0.79) were similar. Amiodarone treated patients receiving the 4/5 day preoperative regimen had a reduced incidence of AF (19.6% vs. 38%, p = 0.013), while those receiving the 1-day preoperative regimen showed a trend (25% vs. 38%, p = 0.06) vs. placebo.

Conclusions: In an elderly population undergoing CTS, Amiodarone prophylaxis reduces AF, the incidence of symptomatic AF, cerebrovascular accident and ventricular tachycardia.