Bridge to Pediatric Heart Transplantation Using Mechanical Circulatory Support: An Analysis \\of the UNOS Database

Abstract

Purpose Pediatric patients awaiting orthotopic heart transplantation (OHT) face increasing wait-list times and often require mechanical circulatory support (MCS) as a bridge to transplantation (BTT). Post-transplant outcomes in this this group have not been well described. Methods and Materials A retrospective review of the United Network of Organ Sharing database was performed to identify pediatric patients requiring MCS as a BTT. Patients were stratified into 3 groups: extracorporeal membranous oxygenation (ECMO), ventricular assist device (VAD) and direct transplantation (DTXP). The primary outcome was survival. Results From 2004 to 2011, 1,997 pediatric patients underwent OHT. There were 389 patients BTT with MCS (19.5%) and 1,608 with DTXP. There were 228 VAD BTT (58.6%) and 161 ECMO BTT (41.4%). Compared to VAD BTT, patients with ECMO BTT were younger (2.9 vs 9.2 years, p Fig. 1 ). In multivariate analysis, ECMO BTT (OR 5.1, p=0.001) and functional status at the time of transplant (OR 0.98, p=0.002) were found to be independent predictors of mortality. Conclusions This review represents the largest survival analysis of BTT with MCS for pediatric OHT. Patients with ECMO BTT were smaller and younger than those with VAD BTT and had significantly poorer survival than those with direct transplantation. Importantly, however, the use of VAD for BTT did not worsen post-transplant survival.