Heart Allocation Change and Multiple Temporary Circulatory Support as Bridge-to-Bridge

Introduction: We investigated how the 2018 Organ Procurement and Transplantation Network heart allocation policy change was associated with changes in characteristics and outcomes of candidates receiving multiple temporary mechanical circulatory support (mtMCS) devices.

Materials and methods: We included adult heart transplant candidates listed October 2014-January 2018 and October 2018-January 2022 in the United Network of Organ Sharing dataset. Prepolicy and postpolicy mtMCS recipients were compared at listing, transplant, 90-days, and 1-year post-transplant. Time between first and second devices and time between first device and transplant were modeled via multivariable linear regression. Transplantation likelihood was modeled using competing risks analysis.

Results: Postpolicy, a higher proportion of transplant candidates received mtMCS (4% versus 1%, P < 0.001), and received their second device an adjusted 49 d sooner versus prepolicy (P = 0.001). Time to transplant was also an adjusted 35 d shorter postpolicy, with an 80% increased transplantation likelihood versus prepolicy (95% confidence interval: 1.6-1.9, P < 0.001). Postpolicy patients experienced reduced waitlist mortality (8% versus 14%, P = 0.04) with marked improvements in 90-day (93% versus 85%, P < 0.001) and 1-year (88% versus 70%, P = 0.01) post-transplant survival.

Conclusions: Postpolicy mtMCS recipients are more likely to progress to transplantation sooner on the waitlist and their shorter waitlist course together with earlier change to a secondary device was associated with improved post-transplant survival versus prepolicy.