Expanding Donor Heart Utilization Through Machine Perfusion Technologies

Abstract

Purpose of Review Recent advances in donor heart preservation have allowed the utilization of hearts that would typically be discarded due to prolonged ischemic times or donation via the circulatory death pathway. This review will discuss recent advances in donor heart preservation including optimization of machine perfusion technologies and future strategies of potential benefit for the donor heart and transplant outcomes. Recent Findings Improvements in organ preservation strategies have enabled retrieval of donor hearts that were not ideal for static cold storage. Machine perfusion (normothermic and hypothermic) and normothermic regional perfusion have ultimately expanded the donor pool for adult heart transplantation. Xenotransplantation has also incorporated machine perfusion for porcine donor heart preservation. Summary Traditional static cold storage is feasible for non-complex donors and transplants. Machine perfusion has enabled increased donor heart utilization however optimal preservation strategies are dependent on the donor criteria, predicted ischemic times and surgical complexity.

Beyond donation to organ utilization in the USA

“…The TransMedics Organ Care System (OCS) is capable of preserving DCD hearts via normothermic machine perfusion (NMP) [63] typically for 3–6 h [66 ▪ ]. A randomized controlled trial in the USA showed promising recipient outcomes, with comparable 1-year survival rates for DCD hearts preserved by OCS vs. DBD hearts preserved with static cold storage [67 ▪ ].…”

“…TA-NRP involves machine-driven, in-situ blood oxygen reperfusion and heart reanimation following donor cardiac arrest, typically for approximately 1 h, followed by cold storage for upwards of 3 h [71]. TA-NRP can also be paired with NMP [63]. Another advantage of TA-NRP is the ability to provide organ function assessments with the heart in a working state [63,71,72 ▪ ], which may further its potential to broaden heart utilization.…”

“…The TransMedics Organ Care System (OCS) is capable of preserving DCD hearts via normothermic machine perfusion (NMP) [63]…”

“…Recent advancements in perfusion technology [63,64] have enabled DCD heart donation, which could increase heart transplant volume as much as 30% [65]. The proportion of heart transplants from DCD donors has grown sharply since the first case in 2019, accounting for 8.4% of heart transplants in 2022 and, remarkably, eclipsing DCD lung transplants (7.5%) in just 4 years (Fig.…”

“…TA-NRP is an even more recent advancement that also enables DCD heart transplantation [63], and reportedly is less logistically complex and costly than ex-situ machine perfusion [70]. TA-NRP involves machine-driven, in-situ blood oxygen reperfusion and heart reanimation following donor cardiac arrest, typically for approximately 1 h, followed by cold storage for upwards of 3 h [71].…”