Unexpected death in children with severe congenital heart defects in Norway 2004-2016

Updated knowledge on the rates and causes of death among children with severe congenital heart defects (CHDs) is needed to further improve treatment and survival. This study investigated nationwide mortality rates in children with severe CHDs with an emphasis on unexpected mortality unrelated to cardiac intervention.

Data on all pregnancies and live-born children in Norway from 2004 to 2016 were obtained from national registries, the Oslo University Hospital's Clinical Registry for CHDs and medical records. Among 2359 live-born children with severe CHDs, 234 (10%) died before 2 years of age. Of these, 109 (46%) died in palliative care, 58 (25%) died of causes related to a cardiac intervention and 67 (29%) died unexpectedly and unrelated to a cardiac intervention, either before (n=26) or following (n=41) discharge after a cardiac intervention. Comorbidity (38/67, 57%), persistent low oxygen saturation (SaO₂; <95%; 41/67, 61%), staged surgery (21/41, 51%), residual cardiac defects (22/41, 54%) and infection (36/67, 54%) were frequent in children who died unexpectedly unrelated to an intervention. Two or more of these factors were present in 62 children (93%). The medical reports at hospital discharge lacked information on follow-up in many patients who died unexpectedly.

The numbers of unexpected deaths unrelated to cardiac intervention in children <2 years of age without comorbidity were low in Norway. However, close follow-up is recommended for infants with comorbidities, persistent low oxygen saturation, staged surgery or residual cardiac defects, particularly when an infection occurs.