Abstract
BACKGROUND: Dexmedetomidine is commonly used after congenital heart surgery and may be associated with a decreased incidence of postoperative tachyarrhythmias. Using a large cohort of patients undergoing congenital heart surgery, we examined for an association between dexmedetomidine use in the immediate postoperative period and subsequent arrhythmia development. METHODS AND RESULTS: A total of 1593 surgical procedures for congenital heart disease were performed. Dexmedetomidine was administered in the immediate postoperative period after 468 (29%) surgical procedures. When compared with 1125 controls, the group receiving dexmedetomidine demonstrated significantly fewer tachyarrhythmias (29% versus 38%; P<0.001), tachyarrhythmias receiving intervention (14% versus 23%; P<0.001), bradyarrhythmias (18% versus 22%; P=0.03), and bradyarrhythmias receiving intervention (12% versus 16%; P=0.04). After propensity score matching with 468 controls, the arrhythmia incidence between groups became similar: tachyarrhythmias (29% versus 31%; P=0.66), tachyarrhythmias receiving intervention (14% versus 17%; P=0.16), bradyarrhythmias (18% versus 15%; P=0.44), and bradyarrhythmias receiving intervention (12% versus 9%; P=0.17). After excluding controls exposed to dexmedetomidine at a later time in the hospitalization, dexmedetomidine was associated with increased odds of bradyarrhythmias receiving intervention (odds ratio, 2.18; 95% confidence interval, 1.02-4.65). Furthermore, there was a dose-dependent increase in the odds of bradyarrhythmias (odds ratio, 1.04; 95% confidence interval, 1.01-1.07) and bradyarrhythmias receiving intervention (odds ratio, 1.05; 95% confidence interval, 1.01-1.08). CONCLUSIONS: Although dexmedetomidine exposure in the immediate postoperative period is not associated with a clinically meaningful difference in the incidence of tachyarrhythmias after congenital heart surgery, it may be associated with increased odds of bradyarrhythmias.