Outcomes of Mechanical Circulatory Support in Infants with Congenital Heart Disease Listed for Heart Transplant

Purpose Infants with congenital heart disease (CHD) and advanced heart failure are a growing population. We hypothesize that survival to transplant was superior in those infants supported with no MCS compared to those with ventricular assist device (VAD) or extracorporeal membrane oxygenation (ECMO). Methods This retrospective cohort study evaluates data from the 1987-2018 United Network for Organ Sharing (UNOS) database assessing patients Results Analysis included 2755 patients of whom 62% (1705) survived to transplant and 50% (1378) survived from listing to 1-year post transplant. At the time of listing, 86% (2357) were not on MCS, 13% (360) were on ECMO, and 1% (38) on VAD. Average weight at the time of listing was 4.2±2.0 kg, with VAD patients larger (5.1±2.1 kg) than ECMO (4.0±1.5 kg) or no MCS (4.2±2.0 kg) (p=0.003). At the time of listing, 53% of VAD patients, 62% of ECMO patients and 45% of patients without MCS were on inotropic support. In comparison to those patients not on MCS, death prior to transplant was highest for those patients on ECMO at listing, (HR 4.1, 95% CI 3.6-4.8) and equivocal if on VAD at listing (OR 1.6, 95% CI 1.0-2.5). 1-yr post-transplant mortality was higher if on ECMO at transplant (vs. no MCS, HR 4.0, 95% CI 3.0-5.3) but similar if on VAD at transplant (vs. no MCS, HR 1.4, 95% CI 0.8-2.5). Conclusion Infants with CHD listed for OHT have poor outcomes regardless of support modality, with less than 2/3 surviving to transplant and only half surviving to 1-year post-transplant. Patients supported with ECMO have particularly dismal survival, while VAD outcomes are similar to those not requiring MCS. Strategies to effectively improve survival in this high-risk cohort are urgently needed.