A mortality risk score for heart transplants after contemporary ventricular assist device bridging.

BACKGROUND: We sought to derive a risk score for 1-year mortality following orthotopic heart transplantation (OHT) in patients bridged with a contemporary centrifugal left ventricular assist device (LVAD).
METHODS: Adult patients (≥18 years) in the United Network for Organ Sharing database undergoing OHT between 2010 and 2019 who were bridged with a HeartWare or HeartMate III device were included. Derivation and validation cohorts were randomly assigned with a 2:1 ratio. Threshold analysis and multivariable logistic regression were utilized to obtain adjusted odds ratios for 1-year post-OHT mortality. A risk score was generated using these adjusted odds ratios in the derivation cohort and the predictive performance of the composite index was evaluated in the validation set.
RESULTS: A total of 3434 patients were identified. In the derivation cohort, the mean age was 53.5 ± 12.1 years and 1758 (76.8%) were male; 1789 (78.1%) were bridged with a HeartWare device. Multivariable logistic regression revealed that recipient age ≥50 years, bilirubin level ≥2.4 mg/dl, ischemic time ≥4 h, and preoperative hemodialysis predicted 1-year post-transplant mortality. Stratification into risk groups in the validation cohort revealed significant differences in postoperative renal failure, stroke, and short-term mortality. One-year post-transplant mortality was 5%, 6.7%, and 14.8% in the low-, moderate-, and high-risk categories, respectively (p < .001).
CONCLUSIONS: Among patients bridged to OHT with newer generation centrifugal LVADs, older age, increasing bilirubin, longer ischemic time, and pre-OHT dialysis independently predicted post-transplant mortality. The composite risk score based on these factors may assist in patient selection and prognostication in those supported with contemporary LVADs.