Decreased Risk for Rejection in Simultaneous Heart-Kidney Transplant

Background: Simultaneous heart and kidney(SHKTx) is one of the best choice for patient with advanced CKD and ESRD. Recent data and basic science research have suggested that kidney transplant has an immunoprotective effect to heart transplant. In this large retrospective cohort study we reviewed the rejection rate in the heart transplant in patient who received a SHK compared with the ones who had heart transplant alone with CKD/ESRD. Methods: We analyzed the OPTN data that had CKD with heart transplants in the period of 1/1/2020 to 12/31/2023. Our inclusion criteria were adults aged 18 and older who receive solid organ heart transplants with evidence of CKD defined as eGFR being less than 60 or being on chronic dialysis for the HTx and were ABO compatible. Our outcome of interest was Rejection. The aim of this study is to determine in the study population if SHKTx has a better outcome defined as no rejection in all stages of CKD and individual stages of CKD. Multivariable logistic regression was performed to evaluate defined patient survival and heart graft survival while adjusting for recipient, donor, and transplant characteristics. Results: During the study period, there was a total of 19,141Htx and 2,970 of SHKTx. The prevalence of rejection was 19.2% with 3,078 in heart alone and 170 in simultaneous heart kidney. Highly prevalent CKD stages were Stage 3A Moderate CKD with 49.7%. We see better odds for SHKTx for stages 3A (OR 0.43, CI-0.24 and 0.77), stage 3B (OR 0.49, CI-0.33 and 0.70), stage 4 (OR 0.43, CI-0.27 and 0.67) and ESRD stage (OR 0.31, CI-0.21 and 0.45) with significant values. We see similar results for overall, all stages of CKD and only for Stage 5 of CKD were not a higher risk. Conclusion: In this we found that Simultaneous heart and kidney was protective for rejection in the heart transplant compared with heart transplant alone. More studies should be done to determine the long-term benefits and pathophysiology of these findings.