Background: Ischemic-reperfusion injury of the brain is a major adverse event after cardiac surgery, especially when extracorporeal circuits are used. Because brain injury induces local overproduction of activin A, we measured plasma concentrations in children after open heart surgery with cardiopulmonary bypass (CPB) to investigate the potential of measuring activin A for early identification of infants at risk for brain damage.
Methods: We evaluated 45 infants (age <1 year) with congenital heart defects: 36 without overt neurologic injury, and 9 with neurologic injury on day 7 after the surgical procedure. Blood samples were taken before surgery, during surgery before CPB, at the end of CPB, at the end of surgery, and at 12 h after surgery. Neurologic development was assessed before surgery and on postoperative day 7.
Results: Activin A concentrations increased significantly during surgery (P <0.0001) to a maximum at the end of CPB. Infants who developed abnormal neurologic sequelae had concentrations significantly higher (P <0.0001, all comparisons) than patients with normal neurologic outcome at all evaluated times, but not before surgery. Activin A had a sensitivity of 100% (95% CI, 66%-100%) and a specificity of 100% (95% CI, 90%-100%) as a single marker for predicting neurologic abnormalities (area under the ROC curve, 1.0).
Conclusions: Activin A increases in children who experience poor neurologic outcomes after open heart surgery, and its assay may help in early identification of infants at risk for brain damage.