MELD-XI Score Predicts Post-Heart Transplant Survival in Fontan Patients: A PHTS Analysis

Abstract

Purpose As heart transplant (HT) outcomes in Fontan patients have improved, there is interest in identifying markers of liver disease associated with increased mortality. In adults, an elevated Model for End Stage Liver Disease eXcluding INR (MELD-XI) score is associated with worse post-HT outcomes. We evaluated the relationship between MELD-XI scores at transplant and post-HT morbidity and mortality in Fontan patients. Methods The Pediatric Heart Transplant Society Registry was queried to identify pediatric Fontan patients listed for HT from 2005-2017. The MELD-XI score was calculated [MELD-XI= 5.112 x ln(total bilirubin) + 11.76 x ln(creatinine) + 9.44] at time of transplant. Those patients with a MELD-XI score at the time of HT above the 75thpercentile of the entire cohort were classified as the high MELD-XI score cohort; All others formed the low MELD-XI score cohort. Results Of 698 Fontan patients listed, 506 (73%) underwent HT. A score ≥ 11.5 identified the high MELD-XI score cohort. At HT, patients in the high MELD-XI cohort were more likely to be older (12 ±5.0 vs. 10.8 ±4.8 y, p=0.05), listed UNOS Status 1A (82% vs. 72%, p=0.05), on a ventilator (11% vs. 3%, p=0.001) and on ECMO (9.1% vs. 2.6%, p=0.009). There was no difference in time to first infection, treated rejection, CAV or malignancy between groups. However, both allograft and patient survival (Figure) was inferior in the high MELD-XI score cohort (p=0.02 and p=0.01 respectively). Multiphase parametric hazard modeling demonstrated that high MELD-XI score (HR=1.2, p Conclusion Pediatric Fontan patients with high MELD-XI scores and those who require mechanical circulatory support have increased mortality post-HT. Identification of Fontan patients with high MELD-XI scores during patient selection or while awaiting HT allows for active management of this risk factor which may reduce post-HT mortality.