Abstract
Early retransplantation following initial orthotopic heart transplantation (OHT) is a rare occurrence, with early evidence suggesting unfavorable clinical outcomes. In October 2018, the United Network for Organ Sharing (UNOS) implemented the current six-tier heart allocation system prioritizing critically ill patients on temporary mechanical support. The impact of this policy change on early retransplantation remains unclear.
We performed a retrospective cohort study using the UNOS database to identify adult patients who underwent cardiac retransplantation within 30 days of their initial OHT between 2014 and 2023. Patients were stratified by the allocation era into two 5-year periods: prior (pre-October 2018) and current (post-October 2018) era. Clinical variables were compared at both the initial and retransplant timepoints. The primary outcome was one year survival following retransplantation.
Fifty-nine patients met inclusion criteria, 17 (28.8%) retransplanted in the prior era and 42 (71.2%) in the current era. There were significantly more early re-transplanted patients in the current era (42 (0.27%) vs 17 (0.14%), p=0.046). Patients in the current allocation era were significantly older (55.9 vs 40.8 years, p = 0.001), more frequently male (76.2% vs 35.3%, p = 0.008), and had a higher prevalence of diabetes (31.0% vs 5.9%, p = 0.048). The use of ECMO (p = 0.424), LVAD (p = 1.0), IABP (p =1.0), ventilatory support (p = 0.873), and inotropes (p = 0.116) at the time of retransplantation did not differ significantly between the prior and current eras. Overall, 1-year survival following retransplantation was 55.9%, with 64.7% survival in the prior era versus 52.4% in the current era (p = 0.46). Mean time to death after retransplantation was non-significantly longer in the current era (74.7 vs 38.7 days, p = 0.542).
Early cardiac retransplantation is performed in patients with very high acuity and is associated with poor outcomes. Since the 2018 allocation policy change, early retransplantation has become increasingly common, but the outcomes remain very poor with approximately 50% of them not surviving to the first year. These findings highlight important ethical considerations regarding organ allocation and candidate selection when considering early retransplantation.