Abstract 13699: Time to Surgery and Preoperative Cerebral Oxygenation Predict Postoperative Ischemic Injury in Hypoplastic Left Heart Syndrome
Introduction: Neurodevelopmental dysfunction is the most common and most disabling long-term consequence of infant heart surgery. Underlying this dysfunction is a high prevalence of hypoxic-ischemic white matter injury, termed periventricular leukomalacia (PVL). The prevalence of PVL in infants with hypoplastic left heart syndrome (HLHS) is particularly high. Identifying risks for PVL may lead to new therapeutic algorithms aimed at prevention.
Methods: Term neonates with HLHS from a larger prospective study were examined retrospectively. Pre- and post-operative brain MRIs were performed. Frequency domain diffuse optical spectroscopy and diffuse correlation spectroscopy were employed to noninvasively quantify cerebral oxygen saturation (ScO2) and cerebral blood flow immediately prior to surgery. PVL was assessed on T1 sequences acquired volumetrically. Manual segmentations were used to calculate PVL volumes. Volumes greater than 150 mm3 were empirically described as clinically significant.
Results: We studied 37 neonates with HLHS and HLHS variants. The average gestational age was 38.0±0.8 weeks and 19/37 were male. Clinically significant PVL was seen in 3/37 (8%) preoperatively and new or worsened postoperative injury was seen in 14/37 (38%). Time from birth to surgery and preoperative ScO2 significantly predicted the amount of postoperative PVL. Those neonates who underwent surgery on day of life 4 or sooner developed significantly less PVL between the two MRIs than those neonates who were operated upon day of life 5 or later (p<0.0001). A significant and negative linear relationship (R2=-0.41, p<0.05) between day of life and ScO2 was observed, suggesting that deteriorating cerebral oxygenation prior to their corrective cardiac surgery may contribute to the increased risk for PVL.
Conclusions: The risk of postoperative PVL in neonates with HLHS significantly increases with longer time to surgical repair and with lower cerebral oxygen saturations.
- © 2013 by American Heart Association, Inc.