Prophylactic Effects of Metoprolol on the Prevention of Atrial Fibrillation after Cardiac Surgery Are Dose Dependent

Atrial fibrillation (AF) is one of the most common complications after cardiac surgery. Many studies have reported an incidence of 20%-40% in patients undergoing open heart surgery, and the peak incidence usually occurs between the postoperative days [Fuller 1989; Aranki 1996; Svedjeholm 2000; Maisel 2001]. AF is commonly self-limited and rarely results in postoperative death. However, postoperative AF (POAF) is often associated with complications, including stroke, heart failure, prolonged hospital stay, and increased costs [Maisel 2001; Bramer 2010]. Many pharmacological methods have been used to prevent this complication, and beta-blockers, which have been investigated in several studies, have demonstrated effectiveness [Ali 1997; Connolly 2003; Crystal 2004; Halonen 2006; Imren 2007]. There is currently a consensus in the use of beta-blockers for the prevention of POAF. However, whether the effect of beta-blockers on POAF is dose dependent has not been widely studied [Coleman 2004; Lucio 2004]. In addition, patients with different racial backgrounds have a different response to metoprolol based on body shape. In addition, the CYP2D6 genotypes are different among white and Asian patients. In this study dose-dependent prophylactic effects of beta-blockers, which were obtained in a single center.