title: Preoperative brain injury in transposition of the great arteries is associated with oxygenation and time to surgery, not balloon atrial septostomy.
abstract: BACKGROUND
  Preoperative brain injury is an increasingly recognized phenomenon in neonates with complex congenital heart disease. Recently, reports have been published that associate preoperative brain injury in neonates with transposition of the great arteries with the performance of balloon atrial septostomy (BAS), a procedure that improves systemic oxygenation preoperatively. It is unclear whether BAS is the cause of brain injury or is a confounder, because neonates who require BAS are typically more hypoxemic. We sought to determine the relationship between preoperative brain injury in neonates with transposition of the great arteries and the performance of BAS. We hypothesized that brain injury results from hypoxic injury, not from the BAS itself.
  
  
  RESULTS
  Infants with transposition of the great arteries (n=26) were retrospectively included from a larger cohort of infants with congenital heart disease who underwent preoperative brain MRI as part of 2 separate prospective studies. Data collected included all preoperative pulse oximetry recordings, all values from preoperative arterial blood gas measurements, and BAS procedure data. MRI scans were performed on the day of surgery, before the surgical repair. Of the 26 neonates, 14 underwent BAS. No stroke was seen in the entire cohort, whereas 10 (38%) of 26 patients were found to have hypoxic brain injury in the form of periventricular leukomalacia. Periventricular leukomalacia was not associated with BAS; however, neonates with periventricular leukomalacia had lower preoperative oxygenation (P=0.026) and a longer time to surgery (P=0.028) than those without periventricular leukomalacia.
  
  
  CONCLUSIONS
  Preoperative brain injury in neonates with transposition of the great arteries is associated with hypoxemia and longer time to surgery. We found no association between BAS and brain injury.
authors.affiliation: Division of Cardiology, Department of Pediatrics, The Children's Hospital of Philadelphia and the University of Pennsylvania School of Medicine, Philadelphia, Pa, USA. cjpetit@texaschildrenshospital.org
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Petit
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Rome
authors.forename: Gil
authors.initials: G
authors.lastname: Wernovsky
authors.forename: Stefanie E
authors.initials: SE
authors.lastname: Mason
authors.forename: David M
authors.initials: DM
authors.lastname: Shera
authors.forename: Susan C
authors.initials: SC
authors.lastname: Nicolson
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Montenegro
authors.forename: Sarah
authors.initials: S
authors.lastname: Tabbutt
authors.forename: Robert A
authors.initials: RA
authors.lastname: Zimmerman
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Licht
mesh_terms: D002404:Catheterization / Q000009:adverse effects / Q000706:statistics & numerical data; D005260:Female; D005865:Gestational Age; D006325:Heart Atria / Q000601:surgery; D006344:Heart Septal Defects, Atrial / Q000453:epidemiology / Q000601:surgery*; D006345:Heart Septal Defects, Ventricular / Q000453:epidemiology / Q000601:surgery; D006346:Heart Septum / Q000601:surgery; D006801:Humans; D002534:Hypoxia, Brain / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D007231:Infant, Newborn; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood*; D011300:Preoperative Care; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D014188:Transposition of Great Vessels / Q000453:epidemiology / Q000601:surgery*
chemical_list: D010100:Oxygen