The impact of changes in renal function during waitlist time on outcomes after heart transplantation

Background and aim: This study evaluated the impact of changes in renal function during the waitlist period on posttransplant outcomes of orthotopic heart transplantation (OHT).

Methods: The United Network for Organ Sharing registry was used to identify adult patients undergoing isolated OHT from 2010 to 2020. Patients were stratified by whether their National Kidney Foundation chronic kidney disease (CKD) stage improved, worsened, or remained unchanged between listing and transplantation. Univariate analysis and multivariable Cox regression were conducted to determine whether a change in estimated glomerular filtration rate (eGFR) or change in CKD stage predicted 1-year mortality after OHT.

Results: Of 22,746 patients, the majority of patients remained in the same CKD stage (59.6%), and the frequencies of patients progressing to improved (19.3%) and worsened (21.1%) CKD stages were similar. Temporary mechanical circulatory support (MCS) was associated with improved CKD stage and durable MCS with worsened CKD stage (p < .001). Post-OHT dialysis was most common in patients with worsened CKD stage (13.2%) and least common in the improved cohort (9.4%) (p < .001). Kaplan-Meier unadjusted 1-year survival rates after OHT were similar between CKD change groups (log-rank p = .197). Multivariable analysis demonstrated no risk-adjusted effect of change in eGFR (p = .113) or change in CKD stage (p = .076) on 1-year mortality after OHT.

Conclusions: Approximately 20% of patients improve CKD stage and 20% worsen CKD stage between listing and OHT, with the remaining 60% having unchanged CKD stage. Worsening CKD stage predicts increased likelihood of post-OHT dialysis, but CKD stage change does not predict 1-year survival following OHT.