Abstract 16305: Closing the Disparities Gap for Heart Transplant Patients Bridged to Transplant With Temporary Mechanical Circulatory Support

Background: There are known disparities in waitlist outcomes by race and sex among patients bridged to heart transplant (BTT) with durable mechanical circulatory support (MCS). With the increasing use of temporary MCS devices (tMCS), we examined waitlist and post-transplant outcomes of patients who had BTT with tMCS.

Methods: Data from the United Network for Organ Sharing (UNOS) database was used to identify patients BTT with tMCS between 2008 and 2018. Patients were stratified by race and sex. Primary outcomes were waitlist mortality within 1 year of listing and 1 year post-transplant mortality among those who successfully reached transplant. Survival was examined with the Kaplan Meier method and Cox proportional hazard modeling.

Results: A total of 997 patients received tMCS as BTT, including 606 white, 203 Black, 119 Hispanic, 56 Asian, 13 other race, and 302 (30%) female patients. Baseline hemodynamics were comparable among groups. Waitlist mortality within 1 year of listing was 35.8% overall and similar for all races (p=0.418) and both sexes (p=0.617). Among those who successfully reached transplant, there were no differences in 1 year post-transplant survival by race (p=0.722) or sex (p= 0.475). On multivariable Cox proportional hazard modeling, neither race nor sex was associated with waitlist or post-transplant mortality (p=NS). Level of education (<high school) was independently associated with 1 year waitlist mortality (HR 1.49, 95% CI 1.06 - 2.06). History of diabetes (HR 1.38, 95% CI 1.07-1.74) and post-transplant dialysis (HR 1.66, 95% CI 1.18-2.29) were associated with 1 year post transplant mortality.

Conclusions: Unlike in BTT with durable MCS, we did not find differences in outcomes associated with race and sex among patients BTT with tMCS. Given the sharp increase in tMCS use after the 2018 U.S. allocation change, it will be important to closely monitor that access to transplantation and outcomes of BTT with tMCS patients continue to be equitable.