Validating patient prioritization in the 2018 Revised United Network for Organ Sharing Heart Allocation System: A...

The 2018 Revised United Network for Organ Sharing Heart Allocation System (HAS) was proposed to reclassify status 1A candidates into groups of decreasing acuity; however, it does not take into account factors such as body mass index (BMI) and blood group which influence waitlist (WL) outcomes. We sought to validate patient prioritization in the new HAS at our center. We retrospectively evaluated patients listed for heart transplantation (n = 214) at Emory University Hospital from 2011 to 2017. Patients were reclassified into the 6-tier HAS. Multistate modeling and competing risk analysis were used to compare outcomes of transplantation and WL death/deterioration between new tiers. Additionally, a stratified sensitivity analysis by BMI and blood group was performed. Compared with tier 4 patients, there was progressively increasing hazard of WL death/deterioration in tier 3 (HR: 2.52, 95% CI: 1.37-4.63, P = .003) and tier 2 (HR: 5.03, 95% CI: 1.99-12.70, P < .001), without a difference in transplantation outcome. When stratified by BMI and blood group, this hierarchical association was not valid in patients with BMI ≥30 kg/m² and non-O blood groups in our cohort. Therefore, the 2018 HAS accurately prioritizes the sickest patients in our cohort. Factors such as BMI and blood group influence this relationship and iterate that the system can be further refined.