Annals of cardiothoracic surgery最新文献

Background: Normothermic ex situ heart perfusion (ESHP) has increased the donor pool with hearts donated after circulatory death (DCD), but functional assessment during ESHP using lactate trends is suboptimal. This study presents the clinical use of high-resolution cardiac mapping to assess electrical function of human DCD hearts on ESHP, where low-voltage-areas might be indicative of myocardial injury.

Methods: Hearts were procured following circulatory arrest of the donor and restarted on normothermic ESHP. DCD hearts were transported to the recipient hospital and lactate concentrations were regularly measured in the perfusate. High-resolution epicardial mapping of the left (LV) and right ventricle (RV) was performed with a 192-electrode array during normothermic ESHP prior to transplantation. Unipolar potential voltages and slopes, conduction velocity and the amount of low-voltage potentials and conduction block were calculated from these recordings.

Results: Electrical mapping was performed on ten DCD hearts transported on ESHP with sequential cardiac transplantation, showing safety and feasibility of the technique. Median potential voltage of the LV and RV was 15.7 mV (14.0-17.4 mV) and 11.3 mV (8.3-11.9 mV) respectively, and low-voltage potentials were minimally present. In comparison, the electrical function of one rejected heart with increasing lactate trend did not differ from the transplanted hearts.

Conclusions: High-resolution electrical mapping of DCD hearts on ESHP may serve as novel additional diagnostic tool for assessing graft function, especially in marginal donors.

In the last decade, heart transplants using allografts from adult donors after circulatory death, in a controlled setting, controlled donation after circulatory death (cDCD) have been rapidly adopted and widely performed. The selection of retrieval methods has largely been determined by state or institutional guidelines concerning permissible postmortem procedures. A significant majority of cDCD heart recoveries have employed direct procurement and perfusion (DPP) followed by normothermic machine perfusion (NMP) for graft preservation. Another established method involves the thoracoabdominal normothermic regional perfusion (taNRP), which is then followed by either NMP or static cold storage. Processing, management and surgical techniques of heart allograft procurement after cDCD are herein described and discussed.

Background: Although it has been widely recognized that heart transplantation (HT) following donation after circulatory death (DCD) can be a successful strategy to expand the donor pool, its clinical outcomes compared to donation after brain death (DBD) are still the subject of intense investigation. We reviewed the clinical characteristics of HT after DCD from the three largest multicenter nationwide registries, highlighting technical aspects, donor and recipient selection, and early outcomes. Moreover, we performed a meta-analysis of survival outcomes of DCD vs. DBD using reconstructed individual patient time-to-event data.

Methods: The PubMed, Web of Science, and Scopus databases were searched in January 2024 to identify the most recent reports from three large multicenter nationwide registries (United States, United Kingdom, and Australia) of HT after DCD. Clinical characteristics were summarized using descriptive statistics, and survival curves were reconstructed for DBD using individual patient time-to-event data. The pooled hazard ratio (HR) with confidence interval (CI) was calculated via Cox regression.

Results: A total of 646 DCD HT patients and 7,253 DBD controls were included in this review. In the majority of cases, donors were young males. The mean age of recipients ranged from 48 to 57 years, and the majority were males with idiopathic dilated cardiomyopathy. Up to 40% of patients required postoperative mechanical circulatory support with extracorporeal membrane oxygenation (ECMO). The meta-analysis estimated a pooled 1-year survival of 91.1% (95% CI: 88.6-93.7%) and 90.1% (95% CI: 89.4-90.8%) for DCD and DBD patients, respectively (P=0.91), with a pooled HR of 0.88 (95% CI: 0.65-1.20).

Conclusions: Although the generally more favorable clinical profile of DCD donors and recipients may constitute a potential selection bias, our meta-analysis documented similar early and medium-term survival outcomes for DCD and DBD HT.

Donation after circulatory death (DCD) presents both opportunities and challenges in the realm of heart transplantation. Its emergence holds promise for narrowing the gap between patients in need of organs and the available donor pool. The rapid emergence of DCD use has allowed heart transplant volume to increase worldwide. Long-term outcomes and best practices remain to be defined and are important considerations in the wider use of these techniques in a broad selection of patients to understand best use and practice moving forward. Expanding DCD donation entails substantial resource allocation, coordination efforts, and training initiatives. Moving forward, standardization is imperative, particularly in aspects such as "stand-off" time, warm ischemic time (WIT), and perfusate composition.

Background: In the current era of heart transplantation, machine perfusion strategies are emerging as potential additions to the armamentarium of a transplant unit. Donation after circulatory death (DCD) donor hearts assessed through normothermic machine perfusion (NMP) has helped expand the donor pool. Hypothermic machine perfusion (HMP) is emerging as an alternative strategy to traditional static cold storage (SCS) when a prolonged ischemic time is anticipated in brain dead (BD) donors, this is important in Australia where long distant procurement is vital. In this study we examine the outcomes in our unit where both forms of machine perfusion (NMP and HMP), as well as SCS is utilized for donor heart preservation, with a particular focus on severe primary graft dysfunction (sPGD) and mortality.

Methods: The year 2021 represents the year when both forms of machine perfusion were available to our unit. Heart transplants in our unit from January 2021 to February 2024 were categorized into three groups for retrospective analysis: (I) DCD-NMP group (n=44); (II) BD-HMP group (n=38), and (III) BD-SCS group (n=78).

Results: There were no significant differences in the mean donor and recipient ages between the three groups. Donor preservation time in the BD-HMP group was significantly longer than the donor ischemic time in the BD-SCS group, and organ care system (OCS) run time in the DCD-NMP group (361±89 vs. 208±47 and 249±49 min respectively, P<0.001). For DCD-NMP, BD-HMP and BD-SCS groups respectively: 30-day survival was: 100%, 97% and 100%; 1-year survival was: 94%, 90% and 94%; 2-year survival was: 90%, 90% and 89% (P=0.9). There was no significant difference in the incidence of sPGD between the three groups (DCD-NMP: 7%, BD-HMP: 5%, and BD-SCS: 5%, P=0.9).

Conclusions: Machine perfusion strategies represent important additions to the modern transplant unit and can expand the donor pool. Results are encouraging with no differences in 2-year survival or incidence of sPGD across the preservation modalities: DCD-NMP, BD-HMP, and BD-SCS.