Interaction between donor obesity and prolonged donor ischemic time in heart transplantation

Abstract

Background: The purpose of the study was to determine the impact of donor obesity on outcomes following heart transplantation in the setting of routine (<4 h) and prolonged (≥4 h) organ ischemic times.

Methods: Retrospective review of the 2000-2020 United Network for Organ Sharing Database was performed to identify adult heart transplant recipients and donors. Nearest-neighbor propensity score matching by donor obesity was performed separately among routine and prolonged cohorts, with Kaplan-Meier survival estimates used to assess survival at 5 years following transplantation.

Results: A total of 43,304 heart transplant recipients were included in analysis, with 15,925 (36.8 %) receiving obese donor hearts. After propensity-score matching, 30-day mortality and 5-year survival following transplantation were not statistically different between recipients of obese and non-obese donor hearts when organ ischemic times were routine. In the setting of prolonged organ ischemic times, those receiving obese donor hearts experienced lower 30-day mortality (5.1 % vs 6.7 %, p = 0.04) and improved 5-year survival (74.9 % vs 71.2 %, p < 0.01) compared to non-obese donor hearts.

Conclusions: Recipients of obese donor hearts experienced improved outcomes compared to those receiving non-obese donor hearts when organ ischemic times exceeded 4 h. These findings suggest that the detrimental impact of prolonged organ ischemic time may be attenuated by donor obesity.

Keywords: Cardiomyopathy; Donor qualities; Heart transplantation; Obesity; Organ ischemic time.