Heart retransplant recipients with renal dysfunction benefit from simultaneous heart-kidney transplantation.

BACKGROUND

Given ongoing donor shortages, appropriate patient selection for dual-organ transplantation is critical. We evaluated outcomes of heart retransplant with simultaneous kidney transplant (HRT-KT) vs isolated heart retransplant (HRT) across varying levels of renal dysfunction.

METHODS

The United Network for Organ Sharing database identified 1189 adult patients undergoing heart retransplantation between 2005 and 2020. Recipients undergoing HRT-KT (n = 251) were compared to those undergoing HRT (n = 938). The primary outcome was 5-year survival; subgroup analyses and multivariable adjustment were performed utilizing the following 3 estimated glomerular filtration (eGFR) groups: <30 ml/min/1.73m, 30-45 ml/min/1.73m, and >45 ml/min/1.73m.

RESULTS

HRT-KT recipients were older and had longer waitlist times, longer inter-transplant periods, and lower eGFR levels. HRT-KT recipients were less likely to require pretransplant ventilator (1.2% vs 9.0%, p < 0.001) or ECMO (2.0% vs 8.3%, p < 0.001) support but were more likely to have severe functional limitation (63.4% vs 52.6%, p = 0.001). After retransplantation, HRT-KT recipients had less treated acute rejection (5.2% vs 9.3%, p = 0.02) and more dialysis requirement (29.1% vs 20.2%, p < 0.001) before discharge. Survival at 5-years was 69.1% after HRT and 80.5% after HRT-KT (p < 0.001). After adjustment, HRT-KT was associated with improved 5-year survival among recipients with eGFR <30 ml/min/1.73m (HR:0.42, 95% CI: 0.26-0.67) and 30 to 45 ml/min/1.73m (HR:0.29, 95% CI 0.13-0.65), but not among those with eGFR>45 ml/min/1.73sm (HR 0.68, 95% CI 0.30-1.54).

CONCLUSION

Simultaneous kidney transplantation is associated with improved survival following heart retransplantation in patients with eGFR <45 ml/min/1.73m and should be strongly considered to optimize organ allocation stewardship.