UNOS Listing Status-Related Changes in Mechanical Circulatory Support Utilization and Outcomes in Adult Congenital Heart Disease Patients

Abstract

<h3>Purpose</h3> The population of adult congenital heart disease (ACHD) patients requiring advanced heart failure therapies is growing. The aim of this study was to investigate the impact of the new United Network for Organ Sharing (UNOS) listing criteria on mechanical circulatory support (MCS) utilization and outcomes in ACHD patients. <h3>Methods</h3> We identified all ACHD (≥18 years) heart transplant candidates in the Scientific Registry of Transplant Recipients database listed during the 590 days prior to (historical cohort) or following (recent cohort) the UNOS allocation revision on October 18, 2018. Patients were grouped based on whether they received central temporary MCS (surgically inserted temporary ventricular assist device [VAD] or extracorporeal membrane oxygenation), peripheral temporary MCS (percutaneous VAD or intra-aortic balloon pump), durable MCS, or no MCS. <h3>Results</h3> A total of 535 patients were included in our study (242 historical, 293 recent). There were no significant differences between the historical and recent cohorts in baseline characteristics. We found no differences in utilization of central temporary MCS (3.31% vs. 3.07%, p=0.88) or durable MCS (3.31% vs. 3.41%, p=0.95), whereas the rate of peripheral temporary MCS increased (2.07% historical vs. 6.83% recent, p=0.009; Figure 1). Across both cohorts, patients supported with peripheral temporary MCS had shorter time-to-transplant than non-supported patients (25.7 vs. 121.7 days, p=0.002). Central temporary MCS patients had greater rates of post-transplant mortality relative to other patients (40.0% vs. 12.6%, p=0.006), while those supported with durable or peripheral temporary MCS had no differences in waitlist (p=0.82) or post-transplant (p=0.32) mortality compared to non-supported patients. <h3>Conclusion</h3> The 2018 UNOS allocation changes increased utilization of peripheral temporary MCS in ACHD patients, decreasing waitlist time without impact on post-transplant outcomes.