Controlled donation after circulatory death (DCD) has become a key strategy for expanding the number of hearts available for transplantation. With the initial question of graft safety now largely resolved, attention has shifted toward identifying which recipients stand to benefit most from this expanded donor pool. 

Patients supported with durable mechanical circulatory support (MCS) represent a particularly relevant group. Although these devices allow patients to remain stable for extended periods, a cumulative risk of infection, bleeding, neurologic events, device dysfunction, and organ deterioration persists throughout support. Moreover, the 2018 revision of the US allocation system lowered the relative priority of many clinically stable patients on durable MCS. Against this backdrop, DCD could offer more than just additional donors — it could also shorten a wait that continues to carry a real clinical cost. 

Wada and colleagues conducted a retrospective analysis of the UNOS database, including adult patients on durable MCS who underwent isolated heart transplantation between 2019 and 2023. They compared recipients of hearts from donors after brain death (DBD) with recipients of hearts from donors after circulatory death (DCD). 

Of 14881 transplants, 3681 were performed in patients on durable MCS: 3374 with DBD grafts and 307 with DCD grafts. DCD recipients spent less time on the waitlist — a mean of 336.9 versus 404.4 days, and a median of 110 versus 175.5 days. Despite longer ischemic times in the DCD group, no significant differences emerged in survival at 6 months (93.2% versus 90.9%) or at 1 year (90.2% versus 89.0%; p = .946), nor in primary graft failure, rejection, dialysis, stroke, or length of hospital stay. Mortality attributed to liver failure was higher with DCD, though based on very few events. After inverse probability weighting to reduce baseline differences between groups, survival remained statistically similar. 

The authors conclude that using DCD donors significantly shortens waitlist time for patients on durable MCS, without a significant difference in early survival. However, the small size of the DCD cohort, the possibility of selection bias, and the lack of detailed information on donors and procurement techniques mean these findings should be interpreted with caution. 

COMMENTARY: 

The main value of this study probably lies not in reconfirming that DCD can deliver good outcomes, but in examining what it adds in a more specific scenario: the patient who has already required durable MCS as a bridge to transplant. 

The most relevant finding is the reduction in waitlist time. DCD recipients waited roughly 67 fewer days on average, and more than two months less by median values. This difference takes on particular weight in patients on durable MCS, since every additional month prolongs exposure to infection, bleeding, neurologic events, device dysfunction, sensitization, and right ventricular or other organ deterioration. The Spanish REGALAD registry has likewise shown that infectious, haemorrhagic, and neurologic complications continue to carry substantial weight during prolonged support. 

The clinical relevance of DCD, then, is not simply about transplanting sooner — it is about shortening the period during which the patient remains exposed to the cumulative risks of mechanical support. Consistent with this, the study found a higher rate of pretransplant infection in the DBD group, precisely the group that spent longer on the waitlist. The authors themselves suggest that a longer wait may have contributed to this difference. 

There is also a paradox at play here. Durable MCS restores haemodynamic stability and organ function, helping patients reach transplant, yet that same stability can lower their relative priority within certain allocation systems. The patient is well enough to wait, even though that wait is not without consequence. Expanding the donor pool through DCD could allow transplantation to happen before a device-related complication forces an escalation in urgency status. 

This point connects to a concept that is especially relevant in transplantation today: the window of opportunity. As recently highlighted at the SECCE Congress, the goal should not be to wait until a device-related complication raises a patient’s priority, but rather to help the patient reach transplant before developing infection, renal failure, prolonged mechanical ventilation, or multiorgan deterioration. Seen this way, expanding the donor pool through DCD may offer value beyond simply shortening the waitlist — it may allow transplantation to occur under better clinical conditions. 

How applicable these results are to our setting deserves some context. In Spain, the use of durable MCS is considerably lower than in the United States and in several European countries. The REGALAD registry recorded only 263 durable MCS implants between 2007 and 2020 across 22 Spanish centres, and more recent national transplant registries do not allow a precise estimate of what proportion of current recipients reach transplant from durable MCS. This contrasts with high transplant activity overall and the growing weight of DCD, which in 2025 accounted for roughly one-third of all heart transplants performed in Spain. As a result, the durable MCS-to-transplant pathway analysed in this study is far more common in the United States than in Spain. 

This difference limits how directly the findings can be generalized, but it also raises an interesting possibility. In a system like Spain’s, where DCD has substantially expanded the donor pool, its effect could occur even earlier in the pathway: if it shortens waitlist times enough, it might, in some patients, remove the need to implant durable MCS as a prolonged bridge to transplant at all. This is not a conclusion demonstrated by the study, but it is a hypothesis particularly relevant to our care model. 

The study’s second message — the lack of a survival difference — calls for more caution in its interpretation. A 1-year survival of 90.2% with DCD versus 89.0% with DBD is reassuring, particularly given the longer ischemic time of DCD grafts. However, the absence of a statistically significant difference does not amount to proof of equivalence. Only 307 patients received a DCD graft compared with 3374 with DBD, and the post hoc power to detect small survival differences was 0.171. 

Inverse probability weighting strengthens the results but does not eliminate selection bias. During the study period, DCD programs were still expanding, and donor and recipient selection was likely especially careful. DCD donors were also younger, and the type of support device differed between groups, with greater use of HeartMate 3 in the DCD cohort. Statistical adjustment cannot fully correct for unrecorded variables or clinical selection decisions. 

Another important limitation is the limited granularity of the registry regarding the DCD process itself. UNOS does not adequately distinguish the components of ischemic time, nor does it provide complete information on procurement and preservation strategy, including normothermic regional perfusion or direct procurement followed by ex situ perfusion. Grouping all these procedures under a single DCD label oversimplifies an increasingly complex reality: what matters today is not only donor type, but also how the graft is recovered, assessed, and preserved, and which recipient ultimately receives it. 

The higher mortality from liver failure observed with DCD also warrants cautious interpretation. Although statistically significant, only two deaths from this cause occurred in each group, so the higher percentage in the DCD group is driven by its small denominator. Without postoperative haemodynamic data, information on right ventricular function, or detailed characterization of primary graft failure, this finding should be considered exploratory. 

Taken together, the study offers a clinically useful message: DCD may allow patients on durable MCS to be transplanted sooner, without the available data suggesting any decline in early survival. In countries with high use of durable support, this could reduce cumulative exposure to its complications. In Spain, where durable MCS use is much lower and both transplant and DCD activity are high, the question may go a step further: whether expanding the donor pool could help some patients reach transplant without ever needing to travel that path in the first place. 

Ultimately, the goal should not simply be to increase the number of transplants, but to use every new donor to help patients reach their graft sooner and in better clinical condition. 

REFERENCE: 

Wada T, Ho J, Belec A, Dominic J, Kelly D, Miyamoto S, Atluri P. Impact of Donation After Circulatory Death on Waitlist Duration and Early Outcomes in Heart Transplantation for Patients With Durable Mechanical Circulatory Support. Interdiscip Cardiovasc Thorac Surg. 2026 Aug 3;41(8):ivag214. doi: 10.1093/icvts/ivag214.