Impact of post-transplant stroke and subsequent functional independence on outcomes following heart transplantation under the 2018 United States heart allocation system

Abstract

This study evaluates the clinical trends, risk factors, and effects of post-transplant stroke and subsequent functional independence on outcomes following orthotopic heart transplantation under the 2018 heart allocation system. The United Network for Organ Sharing registry was queried to identify adult recipients from October 18, 2018 to December 31, 2021. The cohort was stratified into 2 groups with and without post-transplant stroke. The incidence of post-transplant stroke was compared before and after the allocation policy change. Outcomes included post-transplant survival and complications. Multivariable logistic regression was performed to identify risk factors for post-transplant stroke. Sub-analysis was performed to evaluate the impact of functional independence among recipients with post-transplant stroke. A total of 9,039 recipients were analyzed in this study. The incidence of post-transplant stroke was higher following the policy change (3.8% vs 3.1%, p=0.017). Thirty-day (81.4% vs 97.7%) and 1-year (66.4% vs 92.5%) survival rates were substantially lower in the stroke cohort (p<0.001). The stroke cohort had a higher rate of post-transplant renal failure, longer hospital length of stay, and worse functional status. Multivariable analysis identified extracorporeal membrane oxygenation, durable left ventricular assist device, blood type O, and redo heart transplantation as strong predictors of post-transplant stroke. Preserved functional independence considerably improved 30-day (99.2% vs 61.2%) and 1-year (97.7% vs 47.4%) survival rates among the recipients with post-transplant stroke (p<0.001). There is a higher incidence of post-transplant stroke under the 2018 allocation system, and it is associated with significantly worse post-transplant outcomes. However, post-transplant stroke recipients with preserved functional independence have improved survival, similar to those without post-transplant stroke.