Impact of FWIT on outcomes following DCD heart transplantation

Results from a single-center, retrospective, observational study, evaluating the impact of functional warm ischemic time (FWIT) on outcomes in adult heart transplant recipients receiving donation after circulatory death (DCD) hearts recovered using direct procurement and perfusion (DPP), were published in the Journal of Heart and Lung Transplantation by Khan et al. The primary outcomes were severe primary graft dysfunction (PGD) and all-cause mortality.  

Key data: Among 125 recipients, FWIT was ≤30 minutes in 69.6% and >30 minutes in 30.4%. During a median follow-up of 5.4 years, 24 deaths occurred. Severe PGD occurred in 23.2% of recipients. After adjustment for donor age and total ischemic time, FWIT was not independently associated with all-cause mortality (hazard ratio [HR], 1.11; 95% confidence interval [CI], 0.83–1.46; p = 0.49). There was no significant difference between the ≤30- and >30-minute groups in 1-year survival (88.8% vs 84.4%; p = 0.75), incidence of severe PGD (23.0% vs 23.7%; p > 0.99), or post-transplant mechanical circulatory support (MCS) requirement (23.0% vs 31.6%; p = 0.31). 

Key learning: In this study, FWIT >30 minutes was not associated with significantly worse outcomes than FWIT ≤30 minutes in adults undergoing DCD heart transplantation using DPP. These findings suggest that donor hearts with FWIT >30 minutes should undergo comprehensive evaluation rather than be excluded based on FWIT alone. Larger, multicenter studies are needed to better define the safety and efficacy of prolonged FWIT in DCD heart transplantation.