This study evaluates survival outcomes in children who undergo postcardiotomy extracorporeal membrane oxygenation (ECMO) following congenital heart surgery. Using data from the Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD), the study found that ECMO initiation over 48 hours post-surgery correlated with the poorest outcomes. Postoperative septicemia, cardiac arrest, and neurological injury were strongly linked to mortality, while reintubation and unplanned noncardiac reoperation improved survival.