The myocardial protective effects of adenosine pretreatment in children undergoing cardiac surgery: a randomized controlled clinical trial

Objective: Adenosine pretreatment reduces injury caused by ischemia-reperfusion. To investigate the hypothesis that adenosine pretreatment would modulate injury induced by cardiopulmonary bypass (CPB) and myocardial ischemia/reperfusion, we conducted a randomized controlledtrial ontheeffects of adenosinepretreatment inchildrenundergoingsurgery to repaircongenitalheart defects.Methods:Children undergoing surgery to repair congenital heart defects were randomized to adenosine pretreatment or control treatment. Adenosine pretreatment was performed by infusing a total of 2.45 mg kg 1 of adenosine over 10 min. Serum troponin I was measured pre- and postoperatively. Multiple clinical parameters, including postoperative use of inotropic medicine and duration in the intensive care unit (ICU),wererecorded.Results:Atotalof82patientswereenrolledinthestudy.Therewere42controlpatientsand40patientsintheadenosine pretreatment group. The mean age and weight of the two groups were notsignificantly different, nor were cardiopulmonary bypass and crossclamp times. There were no deaths and severe complications in both groups. The adenosine pretreatment protocol caused significant hypotension but had no significant effect on heart rate. One patient had severe tachycardia shortly after the adenosine pretreatment protocol was completed, and adenosine infusion was continued until CPB was started. Postoperative levels of serum troponin I were greater in the controlpatientsthaninthe adenosinepretreatmentgroup,indicating thatthecontrolgroupsufferedgreatermyocardialinjury.Controlgroup patients required more postoperative inotropic agents than those in the adenosine pretreatment group at 0, 1, and 3 h, indicating that the adenosinepretreatment grouphadabettercardiac function.The adenosine pretreatment group also required significantly less time in the ICU than the control group (3.2 1.2 days vs 3.9 1.2 days, p = 0.013). Conclusions: This study demonstrates that adenosine pretreatment is protective of the myocardium during open-heart surgery in pediatric patients. # 2011 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.