Thoracoabdominal Normothermic Regional Perfusion for Cardiac Procurement

Survival after heart transplants from circulatory-dead versus brain-dead donors: Meta-analysis of reconstructed time-to-event data

BACKGROUND

Heart transplantation (HTx) using donors after circulatory death (DCD) has the potential to significantly boost overall transplant rates. This study aims to reconstruct data from individual studies comparing survival between HTx from DCD recipients and donation after brain (DBD) recipients.

METHODS

MEDLINE, Embase, Scopus, were searched up to August 2024. We included studies that reported a Kaplan-Meier summary of survival comparing DCD and DBD HTx. Digitization of the Kaplan-Meier curves and reconstruction of individual patient data followed by survival analysis that was conducted using R software.

RESULTS

Six studies including a total of 3240 patients (2242 DBD and 998 DCD) were included in the final analysis. There was no significant difference in the overall survival rates between DCD and DBD patients (Hazard Ratio (HR): 1.01, 95 % CI [0.81-1.25], P = 0.91). However, the proportional hazard assumption was violated, deeming such results inconclusive. Time-varying flexible parametric model revealed a significantly declining survival in DCD recipients 3 years after surgery. Landmark analyses further suggest this declining trend in the DCD group at the two-year landmark (HR: 1.67, p = 0.021) and the four-year mark (HR: 2.78, p = 0.002). However, data beyond 6 years is limited. Evidence comparing direct procurement and normothermic regional perfusion is scarce, with no significant survival differences observed.

CONCLUSION

This meta-analysis shows that, despite similar early survival outcomes, DCD heart transplants showed a trend towards a lower long-term survival, with the difference becoming evident around three years post-transplantation. These findings highlight the need for enhanced monitoring and optimized post-transplant care in DCD recipients. Further studies with strict and long-term follow-up are warranted to confirm these results.

Revolutionizing Donor Heart Procurement: Innovations and Future Directions for Enhanced Transplantation Outcomes

Heart failure persists as a critical public health challenge, with heart transplantation esteemed as the optimal treatment for patients with end-stage heart failure. However, the limited availability of donor hearts presents a major obstacle to meeting patient needs. In recent years, the most groundbreaking progress in heart transplantation has been in donor heart procurement, significantly expanding the donor pool and enhancing clinical outcomes. This review comprehensively examines these advancements, including the resurgence of heart donation after circulatory death and innovative recovery and evaluation technologies such as normothermic machine perfusion and thoraco-abdominal normothermic regional perfusion. Additionally, novel preservation methods, including controlled hypothermic preservation and hypothermic oxygenated perfusion, are evaluated. The review also explores the use of extended-criteria donors, post-cardiopulmonary resuscitation donors, and high-risk donors, all contributing to increased donor availability without compromising outcomes. Future directions, such as xenotransplantation, biomarkers, and artificial intelligence in donor heart evaluation and procurement, are discussed. These innovations promise to address current limitations and optimize donor heart utilization, ultimately enhancing transplantation success. By identifying recent advancements and proposing future research directions, this review aims to provide insights into advancing heart transplantation and improving patient outcomes.

Kidney Donation After Circulatory Death Using Thoracoabdominal Normothermic Regional Perfusion: The Largest Report of the United States Experience

BACKGROUND

Thoracoabdominal normothermic regional perfusion (TA-NRP) has been increasingly used for donation after circulatory death (DCD) procurements in the United States. We present the largest report of outcomes of kidney transplants performed using DCD donor grafts perfused with TA-NRP.

METHODS

Adult DCD kidney transplants between 2020 and 2022 in the United Network for Organ Sharing database were included. Donors with ≥50 min between asystole and aortic cross-clamp time in which the heart was also transplanted were considered TA-NRP donors. All other donors were considered direct recovery donors. Multivariable regressions were used to assess delayed graft function, as well as posttransplant survival and all-cause graft failure at 30, 90, and 180 d. A propensity-matched analysis of cohorts matched on donor Kidney Donor Profile Index was performed.

RESULTS

Of the 16 140 total DCD kidney transplants performed during the study period, 306 (1.9%) used TA-NRP. TA-NRP donors were younger ( P  < 0.001) and had lower Kidney Donor Profile Index ( P  < 0.001) compared with direct recovery donors. Recipients receiving grafts recovered using TA-NRP were younger ( P  < 0.001) and more likely to be blood group O ( P  < 0.001). Transplants using TA-NRP had lower likelihood of delayed graft function (adjusted odds ratio 0.22 [95% confidence interval, 0.15-0.31], P  < 0.001) but similar 180-d survival ( P  = 0.8) and all-cause graft failure ( P  = 0.3) as transplants using direct recovery grafts. These inferences were unchanged on propensity-matched analysis.

CONCLUSIONS

Our results demonstrate that kidney transplants using TA-NRP DCD allografts have positive short-term mortality and graft survival outcomes, with significantly decreased rates of delayed graft function compared with direct recovery DCD grafts.