Recent Era Outcomes of Mechanical Circulatory Support in Children With Congenital Heart Disease as a Bridge to Heart Transplantation

The objective of the study is to compare the clinical characteristics, risk factors, and overall survival (waitlist and posttransplant) outcomes in children with congenital heart disease (CHD) bridged to transplantation with either a ventricular assist device (VAD) versus extracorporeal membrane oxygenation (ECMO) versus no mechanical circulatory support (MCS) in the recent era. The study included 2,899 primary heart transplantations in patients <18 years with CHD between 2010 and 2019 from the United Network Organ Sharing database. Patients who had ECMO or VAD at listing or while listed were included, and their waitlist and posttransplant outcomes were compared with CHD patients who did not require MCS. Of all, 464 (16%) had ECMO and 200 (7%) VAD at the time of or during the listing. The VAD utilization increased over the last decade (4% in 2010 to 10% in 2019, p < 0.01). The 90 days post-MCS survival was better with VAD than ECMO (67 vs. 49%, p < 0.01). The transplantability rate at 90 days was decreased with younger age (odds ratio [OR], 0.91; 95% CI, 0.86-0.95), lower body mass index (BMI) (OR, 0.93; 95% CI, 0.89-0.98) and lower albumin <3g/dl (OR, 0.6; 95% CI, 0.53-0.7). The multivariate model predicted that lower BMI (OR, 1.12; 95% CI, 1.06-1.18), pretransplant ECMO (OR, 2.19; 95% CI, 1.39-3.45), and higher bilirubin (OR, 1.15; 95% CI, 0.97-1.36) decreased 1-year posttransplant survival. Patients transplanted with VAD had better 1-year survival than ECMO (88 vs. 70%, p = 0.01). Waiting list survival of children with CHD supported by VAD is better compared to ECMO. The 1-year posttransplantation outcome of CHD patients supported by VAD is similar to the no MCS patients and better than ECMO-supported patients. There is no significant difference in post-HT survival between patients transitioned from ECMO to VAD while listed and those with VAD-first.