Analysis of United Network for Organ Sharing: Neurodevelopmental Outcomes of Mechanical Circulatory Support as a Bridge-to-Transplantation in Pediatric Heart Transplant Recipients

<b>Background:</b> This analysis evaluates the longitudinal impact of extracorporeal membrane oxygenation (ECMO) and ventricular assist device (VAD) on the progression of motor delay and cognitive delay in pediatric heart transplant recipients. <b>Methods:</b> The United Network for Organ Sharing Registry was queried for pediatric patients (<18 years) who received a heart transplant between 2008 and 2022 and were bridged-to-transplantation with either ECMO or VAD. Patients were further stratified based on the progression of delay status pretransplant to post-transplant. <b>Results:</b> A total of 827 patients were included in the final VAD cohort and 68 in the final ECMO cohort with 187/827 (22.6%) and 20/68 (29.4%) having progression of delay, respectively. Patients with progression of delay were more likely than those without progression of delay to have had a stroke prior to discharge (VAD: 14/187 (7.5%) vs. 16/640 (2.5%), <i>P</i> = .003; ECMO: 5/20 (25%) vs. 3/48 (6.25%), <i>P</i> = .043). VAD patients more often developed isolated delays (motor or cognitive only), whereas patients bridged-to-transplantation on ECMO more often had combined delays, with a cumulative incidence of combined delay at 3-years of 20.0% (95% CI = 8.94-34.20). Among VAD supported patients, those with progression of delay had worse 3-year survival compared with those without (91.20% [95% CI = 87.04-95.57%] vs. 94.97% [95% CI = 93.19-96.78], log-rank <i>P</i> = .04). Postoperative stroke was associated with an increased risk of progression of delay (OR = 2.39 [95% CI = 1.13-5.02] <i>P</i> = .021), and progression of delay was found to be an independent predictor of mortality (HR = 2.10 [95% CI = 1.35-3.25], <i>P</i> < .001). <b>Conclusions:</b> While overall rates of neurodevelopmental delay are similar between those bridged-to-transplantation with ECMO or VAD, the type of delay and associated survival varies.