Survival Benefit of Heart-Kidney Versus Heart Transplant With or Without Delayed Kidney Transplant.

BACKGROUND

Simultaneous heart-kidney transplantation (SHKT) or isolated heart transplantation (IHT) benefits patients with end-stage heart disease and kidney dysfunction. Understanding the outcomes, risk factors for post-IHT kidney transplantation, and survival benefits of SHKT compared with those of IHT and kidney-after-heart transplantation can guide clinical decision-making. This study aimed to evaluate IHT outcomes, identify risk factors for post-IHT isolated kidney transplantation, and compare the survival benefits of IHT, SHKT, and kidney-after-heart transplantation.

METHODS

This retrospective study analyzed data from the United Network for Organ Sharing database, spanning 2000 to 2022. Adult patients (aged ≥18 years) who underwent their first IHT (n=48 069) or SHKT (n=2345) were included. Among patients undergoing IHT, 667 (1.4%) subsequently received isolated kidney transplantation. The primary outcome was patient survival, which was visualized by Kaplan-Meier analysis and assessed using the shared-frailty Cox proportional hazards model. Survival rates were compared among IHT, SHKT, and kidney-after-heart transplantation recipients. Logistic regression analysis identified risk factors for post-IHT isolated kidney transplantation.

RESULTS

The recipient's age, body mass index, pre-IHT diabetes, prior dialysis, and estimated glomerular filtration rate were significant risk factors for post-IHT isolated kidney transplantation. Kaplan-Meier analysis showed significantly higher survival with SHKT than with IHT (1-year: 88.0% versus 85.7%; 5-year: 70.5% versus 64.1%; 10-year: 38.1% versus 30.3%; overall P=0.005). Compared with kidney-after-heart transplantation, SHKT tended to show lower short-term survival but higher long-term survival (5-year: 72.1% versus 61.9%, P=0.047; 10-year: 42.9% versus 15.8%, P<0.001).

CONCLUSIONS

Selected patients with end-stage heart disease and kidney dysfunction derive more long-term survival benefit from SHKT than from IHT.