Abstract 11442: Continued ACE Inhibition Alters the Inflammatory and Fibrinolytic Response to Cardiopulmonary Bypass in Children
Background: Many children with a congenital heart defect undergo surgical correction requiring cardiopulmonary bypass (CPB). One sixth of these patients take an angiotensin-converting enzyme inhibitor (ACEi) for heart failure treatment. ACE inhibition attenuates the increase in plasminogen activator inhibitor-1 (PAI-1) following CPB in adults whereas the effect on the inflammatory response is uncertain. The effect of ACE inhibition on the fibrinolytic and inflammatory response in children undergoing CPB is not known. This study tests the hypothesis that preoperative ACE inhibition attenuates postoperative PAI-1 and interleukin (IL)-6 expression following CPB in children.
Methods and Results: We measured the effects of CPB on the fibrinolytic and inflammatory response in 20 children taking an ACEi who were randomized to continue ACEi until the morning of surgery (ACEi group, N=11) or to discontinue it 72 hours prior to surgery (No ACEi group, N=9). Blood samples were taken at baseline before CPB, at 30min of CPB, after protamine administration and on postoperative day 1 (POD1). Baseline bradykinin concentrations were significantly higher and ACE activity was significantly lower in the ACEi group compared to the no ACEi group (P=0.04 and P=0.001 respectively). PAI-1 antigen increased 15-fold following CPB and peaked on POD1 (from 4.6±1.2 to 67.7±9.5 ng/ml; P<0.001). POD1 PAI-1 antigen correlated significantly with CPB time (r2=0.40, P=0.03) and was significantly lower in the ACEi group compared to the no ACEi group (P=0.03). The pro-inflammatory markers IL-6, IL-8 as well as the anti-inflammatory marker IL-10 increased significantly following CPB (all P<0.001). IL-6 concentrations were significantly higher in the ACEi group following CPB (P=0.02).
Conclusion: ACE inhibition attenuates the increase in postoperative PAI-1 but enhances the IL-6 response in children.
- © 2010 by American Heart Association, Inc.