Impact of increased time at the highest urgency category on heart transplant outcomes for candidates with ventricular assist devices

Abstract

Background: Ventricular assist devices (VADs) have improved survival among end-stage heart disease patients. Since 2002, heart transplant candidates with VADs have been afforded 30 days of elective time at the highest urgency category (Status 1A) under Organ Procurement and Transplantation Network (OPTN) policy. We aimed to determine the effect of increasing elective time at the highest urgency category for heart transplant candidates with VADs. This analysis was requested by OPTN during its evaluation of heart allocation policy.

Methods: We simulated several allocation schemes wherein elective Status 1A time was increased to 45, 60, and 90 days; results were compared with a baseline simulation of 30 days and with the actual observed heart transplant waiting list cohort.

Results: The simulations showed that increasing elective Status 1A time for candidates with VADs did not substantially change waiting list mortality overall or for sub-groups of concern, which were candidates with VADs listed at a lower-urgency category (Status 1B), those with with VAD complications, total artificial heart, or intraaortic balloon pump support; or those with extracorporeal membrane oxygenation. Across the different time allowances, the average post-transplant death rate remained stable. It also remained stable for recipients previously listed as Status 1A or 1B categories for VAD and for recipients with VAD complications or an intraaortic balloon pump at transplant, on extracorporeal membrane oxygenation, and those without devices.

Conclusions: Our results suggest that increasing time in the highest urgency category for candidates with VADs would not improve waiting list mortality or post-transplant outcomes for heart transplant candidates overall.

Keywords: OPTN; Status 1A; heart transplant candidate; urgency category; ventricular assist device; waiting list.