Incidence and long-term outcome of heart transplantation patients who develop postoperative renal failure requiring dialysis

Background: Acute renal failure requiring dialysis after heart transplantation remains a significant clinical issue because of its increasing incidence. We aimed to investigate its time trends, clinical predictors, and long-term outcomes. Methods: Adult heart transplantation recipients registered in the United Network for Organ Sharing registry between 2009 and 2020 were identified. The patients were grouped according to the requirement for dialysis in the postoperative heart transplantation period. The independent risk predictors were identified, and the association between post-heart transplantation renal failure requiring dialysis and long-term mortality accounting for re-transplantation was investigated. Results: A total of 28,170 patients were included in the study, of which 3,371 (12%) required dialysis immediately post-heart transplantation. The incidence increased from 7.9% to 13.9% during the study period. Longer ischemic time, serum creatinine at transplantation >1.2 mg/dL, prior cardiac surgery, higher recipient body mass index, support of mechanical ventilation or extracorporeal membrane oxygenation, and history of congenital heart disease or restrictive/hypertrophic cardiomyopathy were its predictors (all p < 0.05). Patients on posttransplant dialysis had a higher risk of all-cause mortality (adjusted hazard ratio [aHR]: 5.2, 95% CI: 4.7-5.7, p < 0.001), 30 day mortality (aHR: 7.7, 95% CI: 6.3-9.6, p < 0.001) and 1 year mortality (aHR: 7.5, 95% CI: 6.6-8.6, p < 0.001). Post-transplant dialysis was associated with a risk of treated rejection at 1 year. Conclusion: Acute renal failure requiring dialysis after heart transplantation is associated with significantly worse 30 day and long-term mortalities, and thus, early identification of high-risk patients is crucial to prevent severe renal complications.