Extended Duration of Ex-Vivo Perfusion is Associated with Worse Survival in Donation After Circulatory Death Heart Recipients: A National Database Analysis.

Abstract

Background: The impact of duration of ex-vivo heart perfusion (EVHP) on patient outcomes following donation after circulatory death (DCD) heart transplantation has not been established.

Methods: Adult first-time DCD heart transplants using EVHP were identified in the Organ Procurement & Transplant Network database (12/2019-09/2023). Total out of body time (OBT) was dichotomized based on perfusion duration exceeding the 90^th percentile of EVHP hearts in the study. The primary outcome of 6-month mortality was assessed using Kaplan Meier curves and multivariable Cox regression. 30-day, 1-year, and 3-year mortality were also assessed. Secondary postoperative outcomes of index hospitalization length of stay, acute rejection, dialysis, and stroke were assessed using univariable linear or logistic regression.

Results: Among 575 recipients of DCD transplantations using EVHP, 58 hearts had extended perfusion times based on an OBT cutoff of 8.3 hours which identified OBT greater than the 90^th percentile. Extended perfusion heart recipients had worse overall mortality at 6 months compared to standard perfusion hearts after adjusting for critical donor and recipient factors [aHR=2.48(1.25,4.93),p=0.009]. Early 30-day mortality was comparable between the groups (p=0.592). However, 1-year and 3-year outcomes showed worse mortality in recipients of extended perfusion hearts (both p<0.05). Post-transplant dialysis requirement and increased length of stay was more likely in the extended perfusion group (both p<0.05). There was no difference in acute rejection(p=0.163), and stroke(p=0.170).

Conclusions: There is a potential detrimental effect of extended EVHP duration on DCD heart recipient survival. Future work will explore the identified opportunity to improve organ preservation during EVHP.