Objectives: VA ECMO has become one important tool to treat patients with chronic cardiomyopathy who are on waiting list for heart transplantation (HT) and acutely worsens and need mechanical support. Some studies showed worse results, but with changes in the allocation system, these patients are designated to higher status, which can impact the outcomes. Our allocation system was modified in 2021. The objective of our study was to analyze the impact of the new allocation system on the results of patients bridged to HT using VA ECMO in a high volume heart transplant center.

Methods: Of the 298 HT performed between 2016 and 2021 in our center, 125 (42%) were in use of inotropic support, 150 (50%) were bridged with  intra-aortic balloon pump and 23 (8%) patients were bridged with VA ECMO. 20 patients were also in ECMO support, but died on waiting list. About 75% of patients bridged with ECMO were during the last 3 years.

Results: Our mean list mortality on ECMO before the new allocation system (2016-2020) was 61.8% and after the new allocation (2021), 28,5%. The mean waiting time on ECMO was 7.2 days with the old system and 4 days after the new system. The survival to hospital discharge was 55% for patients bridged with ECMO in the old system and 80% for patients in the new allocation system. The total operative mortality during the old allocation system was 13,06% and 5.26% in the new allocation system.

Conclusions: The new allocation system positively influenced the mortality of patients bridged with VA ECMO to HT. The waiting list mortality was reduced, the days on ECMO were reduced and the survival to hospital discharge was improved.