Immune Unresponsiveness to Cardiopulmonary Bypass Is Associated With Unfavorable Outcome in Infants Requiring Cardiac Surgery

Cardiopulmonary bypass (CPB) induces a complex immune response which can lead to complications after pediatric cardiac surgery. We hypothesized that analyzing the whole blood transcriptomic response after cardiac surgery with or without CPB in children would provide new insights into the pathophysiological mechanisms of CPB-related postoperative complications. In this study focusing on infants ≤3 months of age requiring CPB who are more likely to develop postoperative complications, we defined an immune transcriptomic signature related to CPB. Among the genes included in the CPB signature, we identified only 18 genes that were differentially expressed after surgery in patients with a complicated outcome. In contrast, more than 2,000 genes were differentially expressed before and after the surgery in the uncomplicated group. We demonstrated the predictive potential of the preoperative plasma TNFSF12 abundance to identify patients at risk of CPB-induced complications, which was confirmed in an external cohort.