Role of Renal Replacement Therapy During the Peri-Transplant Period of Heart Transplantation

Abstract

BACKGROUND Heart transplantation (HT) is the most useful treatment modality for heart failure. Although several studies have reported the impact of acute kidney injury (AKI) on clinical outcomes after transplantation, little is known about the impact of peri-transplant renal replacement therapy (RRT) on clinical outcomes. We compared the clinical outcomes according to RRT use status among patients with AKI during the peri-transplant period. MATERIAL AND METHODS The medical records of 21 patients who underwent HT from January 2006 to May 2019 were reviewed. We assessed the heart failure cause, comorbidities, immunosuppressant type, requirement for extracorporeal membrane oxygenation, AKI incidence, and cardiac and renal functions over time. The patients were divided into 3 groups: those without AKI (non-AKI group, n=6), those who underwent perioperative RRT (RRT group, n=10), and those who did not undergo RRT (non-RRT group, n=5). RESULTS The most common cause of HT was dilated cardiomyopathy (52.4%). Fifteen patients (71.4%) experienced AKI during the peri-transplant period. Among them, 9 (90%) in the RRT group underwent continuous RRT and only 1 (10%) underwent intermittent hemodialysis. Until 6 months after HT, the renal function of the RRT group was worse than that of the non-RRT group (estimated glomerular filtration rate 44.2 vs. 69.2 mL/min/1.73 m2, P=0.015), but the differences dissipated by 9 months. Finally, all patients, even in the RRT group, withdrew from dialysis. CONCLUSIONS RRT during the peri-transplant period in HT may be a good bridge therapy for renal function recovery in patients with cardiorenal AKI.

Figure 1

Cardiac function over time after heart transplantation. There were no statistically significantly differences in left ventricular ejection fraction at 1, 6, and 12 months after heart transplantation. At 3 months after heart transplantation, left ventricular ejection fraction of the RRT group (59.5±2.1%, mean±SD) was significantly lower than that of the non-RRT group (64.2±0.6%, mean±SD) (p=0.008). Left ventricular ejection fraction at 1 month was 61.5±3.9% (mean±SD) in the RRT group and 64.2±4.5% (mean±SD) in the non-RRT group. At 6 months, it was 61.8±3.2% (mean±SD) in the RRT group and 63.5±6.3% (mean±SD) in the non-RRT group. At 12 months, it was 62.5±4.2% (mean±SD) in the RRT group and 52.0±15.0% (mean±SD) in the non-RRT group. P values were calculated using the t test. * P<0.05 was considered statistical significance.

Figure 2

Renal function over time after heart transplantation. (A) There were no statistically significant differences in serum creatinine at 3, 6, 9, and 12 months after heart transplantation. At 1 month after heart transplantation, serum creatinine of the RRT group (1.7±0.8 mg/dL, mean±SD) was significantly higher than that of the non-RRT group (1.1±0.3 mg/dL, mean±SD) (P=0.039). (B) There were no statistically significant differences in CKD-EPI eGFR at 1, 3, 9, and 12 months after heart transplantation. At 6 months after heart transplantation, CKD-EPI eGFR of the RRT group (44.2±14.2 ml/min/1.73 m², mean±SD) was significantly lower than that of the non-RRT group (69.2±14.2 ml/min/1.73 m², mean±SD) (P=0.015). (C) Renal recovery rate over time was not significantly different between the RRT and the non-RRT groups when calculated by the log-rank test (p=0.051). * p<0.05 was considered statistical significance.