title: Timing of diagnosis affects mortality in critical congenital heart disease.
abstract: Screening for critical congenital heart disease (CHD) with prenatal ultrasound or postnatal pulse oximetry has the potential to improve outcome. To guide screening recommendations, this study aimed to identify the proportion and outcome of major CHD diagnosed before (early) or after (late) postnatal discharge prior to the introduction of postnatal oximetry screening.
  
  
  
  A retrospective, population-based review of all major CHD in New Zealand from 2006 to 2010. The timing of diagnosis relative to discharge and to intervention in critical and non-critical cases with intention to treat was determined, as was the relationship of diagnostic timing to mortality at 1 year of age.
  
  
  
  Late diagnosis occurred in 20% of critical and 51% of non-critical cases. Mortality occurred in 18% of critical vs 8% of non-critical cases. Mortality was lower with an early diagnosis of critical CHD (early diagnosis 16% vs late diagnosis 27%, p=0.04). Isolated critical CHD benefited most from early diagnosis (mortality, early diagnosis 12% vs late diagnosis 29%, p=0.002). Early diagnosis occurred in >90% critical complex CHD and hypoplastic left heart syndrome, 85% d-transposition of the great arteries (d-TGA) and 53% critical left ventricular outflow tract obstruction (LVOTO). Deaths in d-TGA and LVOTO primarily occurred prior to intervention and for d-TGA most often when birth was distant from the cardiac centre.
  
  
  
  Excess mortality occurs following late diagnosis of critical CHD, and for d-TGA even with early diagnosis if intervention is not immediately available. Antenatal detection retains an important role in reducing mortality related to critical CHD.
authors.affiliation: Greenlane Paediatric and Congenital Cardiac Service, Starship Children's Hospital, Auckland, New Zealand.
authors.forename: Luke
authors.initials: L
authors.lastname: Eckersley
authors.affiliation: Department of Obstetrics & Gynaecology, National Women's Hospital, Auckland, New Zealand.
authors.forename: Lynn
authors.initials: L
authors.lastname: Sadler
authors.affiliation: New Zealand Maternal Fetal Medicine Network, National Women's Hospital, Auckland, New Zealand.
authors.forename: Emma
authors.initials: E
authors.lastname: Parry
authors.affiliation: Greenlane Paediatric and Congenital Cardiac Service, Starship Children's Hospital, Auckland, New Zealand.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Finucane
authors.affiliation: Greenlane Paediatric and Congenital Cardiac Service, Starship Children's Hospital, Auckland, New Zealand.
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Gentles
mesh_terms: D057210:Delayed Diagnosis; D042241:Early Diagnosis; D006330:Heart Defects, Congenital / Q000175:diagnosis* / Q000401:mortality; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D053208:Kaplan-Meier Estimate; D009520:New Zealand / Q000453:epidemiology; D010092:Oximetry; D018743:Perinatal Care; D012189:Retrospective Studies; D013997:Time Factors; D016216:Ultrasonography, Prenatal / Q000401:mortality
keywords: Cardiac Surgery; Mortality; atrial septal defect; congenital heart disease; delayed diagnosis