Prolonged ECMO and Renal Failure Increase Mortality After Congenital Heart Surgery, finds study

A recent study published in the European Journal of Cardio-Thoracic Surgery found about 2% of patients undergoing congenital heart surgery require extracorporeal membrane oxygenation (ECMO), with an overall survival rate of around 50%. Prolonged ECMO support and Acute Renal Failure requiring renal replacement therapy were independently associated with higher mortality. Mortality rose sharply after 6 days of ECMO, emphasizing the importance of early reassessment and consideration of alternative management strategies.

ECMO is a form of advanced life support that temporarily takes over the function of the heart and lungs. It is commonly used in critically ill patients whose cardiopulmonary systems fail to recover immediately after surgery. By circulating blood outside the body and oxygenating it through a machine, ECMO allows the heart and lungs time to rest and heal.

The study examined all congenital heart surgeries performed at a single medical center from 2001 to 2024, which included a total of 9,892 procedures. This research found that 178 patients (1.8%) required perioperative venoarterial ECMO support following surgery. Although relatively uncommon, the need for ECMO indicates severe postoperative complications and places patients among the most critically ill.

Patients who required ECMO were typically very young with the median age at surgery was 2.8 months, and the median weight was just 4.1 kilograms, reflecting the fragile condition of many pediatric heart patients. Among children aged 2 years or younger, two surgical categories were associated with a higher risk of needing ECMO. One being the Norwood procedure, used to treat hypoplastic left heart syndrome, and the other were surgeries addressing congenital coronary artery malformations.

Once ECMO support began, the median duration of therapy was 6 days. Clinicians were able to successfully wean 62% of patients off ECMO after the first course of treatment. 17% of patients required a second ECMO run, which indicated ongoing or recurrent cardiac instability. The study reported an in-hospital mortality rate of 55% among patients who required ECMO support. Death typically occurred a median of 16 days after surgery.

Model-based projections showed that predicted mortality rose steeply from approximately 26% to 74% between days 6 and 12 of ECMO support. Researchers identified prolonged ECMO duration and acute renal failure requiring renal replacement therapy as independent predictors of death. Overall, the findings reinforce ECMO’s vital role as an emergency support tool while emphasizing the need for careful monitoring and timely decision-making in the most vulnerable pediatric heart patients.

Reference:

Schaeffer, T., Hayat, S., Matsubara, M., Palm, J., Lemmen, T., Heinisch, P. P., Piber, N., Amici, A., Hager, A., Ewert, P., Hörer, J., & Ono, M. (2026). Early outcomes of extracorporeal membrane oxygenation in congenital heart surgery. European Journal of Cardio-Thoracic Surgery: Official Journal of the European Association for Cardio-Thoracic Surgery, ezag123. https://doi.org/10.1093/ejcts/ezag123