Abstract
OBJECTIVES: The Impella microaxial left ventricular assist device (Abiomed) is increasingly used in adults as extended support bridging to heart transplantation. In recent years, its off-label use in children has also expanded. This review summarizes current experiences with Impella support in pediatric patients listed for heart transplantation and compares outcomes with contemporaneous cohorts who either received no support or other ventricular assist device support. METHODS: We analyzed data from the United Network for Organ Sharing registry between January 2018 and July 2024, including all children listed for heart transplantation. Longitudinal outcomes were assessed using Kaplan-Meier analysis, with comparisons made between children supported with Impella, those receiving other device support, and those managed without mechanical support. RESULTS: Impella utilization increased steadily over time. The Impella cohort included 59 children, with a median age of 14 years (interquartile-range 13-16) at listing and 15 years (interquartile-range 13-16) at transplant. The underlying pathologies were: cardiomyopathy (75%,n=44), congenital heart disease (14%,n=8), and other conditions (12%,n=7). Impella device types used were: 5.0/5.5 (59%,n=35), CP (33%,n=20), and RP (8%,n=4). Ten patients (17%) were converted to durable ventricular assist device with a median support of 5 days (interquartile-range 2-11). Forty-two patients (71%) received transplantation while on Impella support (median 15 days, interquartile-range 8-22). Five patients (8%) died while awaiting transplantation. Among those who received transplantation, four deaths occurred during follow-up. Three-year post-transplant survival was not statistically significantly different for children who received Impella, other device, and no device prior to transplantation. CONCLUSION: Impella use in children as a bridge to heart transplantation has increased, with favorable early outcomes. The Impella 5.5 has contributed to this trend, likely due to its high-flow capacity and mobility potential. Further assessment of its advantages, efficacy, and safety is needed.