Cardiac Outcomes in Isolated Heart and Simultaneous Kidney and Heart Transplants in the United States

INTRODUCTION: Kidney dysfunction is not uncommon in patients with advanced heart failure. Simultaneous kidney and heart transplants (SKHTs) have gained acceptance as a treatment for patients with end-stage heart failure and severe kidney dysfunction. United States saw a rise of 650% in SKHT from 2000 to 2019. Despite increasing number of SKHT, the selection criteria remain poorly defined and vary across transplant centers. METHODS: We evaluated patient and cardiac allograft survival for SKHT and heart transplant alone (HTA) using the United Network for Organ Sharing (UNOS) database. We then performed a subgroup analysis in recipients with post-transplant acute kidney injury requiring renal replacement therapy (RRT) and compared outcomes between SKHT and HTA recipients. RESULTS: Although patient survival was comparable between SKHT and HTA groups (12.4 vs. 11.3 years), patients dependent on dialysis pretransplant derived greater survival advantage from SKHT as compared with HTA (12.4 vs. 9.9 years). Cardiac graft survival was better in SKHT (12.5 vs. 11.2 years). Among patients who developed acute kidney injury requiring RRT postoperatively, SKHT recipients had a significantly better survival (11.9 vs. 2.7 years). CONCLUSION: Our data support consideration of SKHT in dialysis-dependent heart transplant candidates and suggest that patients who are at increased risk of requiring RRT after heart transplant may benefit from SKHT.