Very Temporary Mechanical Support Prior to Heart Transplant: Post-Transplant Outcomes as Status 1-2 versus 3-6 in the Setting of Short Wait Times

Abstract

<h3>Purpose</h3> With the introduction of the new heart allocation system, controversy persists over the potential negative impact of the use of temporary mechanical support (tMCS) prior to heart transplant (HT). However, the risks of tMCS may be mitigated in the setting of short wait times. <h3>Methods</h3> All patients with HT at a single institution from 10/20/18 - 10/26/20. Patients were categorized as tMCS (Status 1-2) or controls (Status 3-6). Multiorgan transplants were excluded. <h3>Results</h3> A total of 126 patients were included and received HT: Status 1 - 9 (7.1%), Status 2 - 45 (35.7%), Status 3 - 40 (31.8%), Status 4 - 19 (15.08%), Status 5 - 0, Status 6 13 (10.3%). Therefore, the tMCS group (Status 1-2) had 54 patients (43%) and the controls (Status 3-6) 72 patients (57%). Baseline characteristics were not different for groups: mean age 53 years, 80% male, and 54% white. Blood groups were not different: A 36%, B 15%, AB 5%, O 44%. Donor race was not different between groups and was 59% white. For tMCS compared to controls, donors were more likely to be male 82% v. 60%, p=0.009 and were younger 31 v. 37 years, p=0.008. Overall median time from listing to transplant was 9 days. The median time from listing to transplant for Status 1 was 5 days, Status 2 was 6.5 days, Status 3 was 16.5 days and Status 4-6 was 26 days. One-year survival was excellent and not significantly different for tMCS compared to controls, 97.7% v. 91.5%, p=0.18 (Figure 1). <h3>Conclusion</h3> The new heart allocation system prioritizes patients with tMCS and in the setting of short waiting times, there may be less exposure to the risks of tMCS. With a median time to HT of less than one week for tMCS, the one-year survival for patients supported with tMCS is excellent and not significantly different from those who are Status 3-6.