Waitlist mortality risk (US-CRS score) distribution among status 1 and 2 adult heart transplant candidates with exceptions.
4 affiliations
- 1Department of Surgery, NYU Grossman School of Medicine, New York, New York.
- 2Department of Medicine, University of Minnesota, Minneapolis, Minnesota.
- 3Department of Cardiothoracic Surgery, NYU Grossman School of Medicine, New York, New York.
- 4Department of Medicine, University of Chicago, Chicago, Illinois.
Abstract
The US-candidate risk score (US-CRS) predicts waitlist mortality among heart transplant candidates using 7 laboratory, cardiovascular, and cardiac device usage variables on a 50-point scale, with higher scores indicating greater mortality risk. We assessed whether US-CRS accurately assigns mortality risk for exception candidates, and whether the alignment of allocation priority with waitlist mortality risk (US-CRS) differs between candidates with and without exceptions. We compared the performance of US-CRS in candidates with and without exceptions using receiver operating curves. We compared US-CRS distributions using the Kolmogorov-Smirnov (KS) test and examined the proportion of candidates below specific score thresholds in each group. We also compared candidates with and without exceptions using Wilcoxon Rank-Sum test for continuous variables and Pearson's Chi-squared test or Fisher exact test for categorical variables. US-CRS is accurate for measuring mortality risk among exception candidates as it is among non-exception candidates. Patients with higher waitlist status had higher median US-CRS. However, the median US-CRS of Status 1 candidates without exceptions (50 [IQR 48-50]) was significantly higher than for candidates with exceptions (45 [36-48]; [ p≤0.05 ]), and similarly for Status 2 (46 [41-49] vs. 42 [32-47]; [ p≤0.05 ]). Notably, 33.13% of Status 1 and 41.28% of Status 2 candidates with exceptions had US-CRS below 40, compared to only 1.84% and 19.20% of candidates without exceptions, respectively. Conversely, among candidates in Status 3 and 4, candidates with exceptions generally had higher US-CRS than candidates without exceptions. Allocation priority under the status system does not align with estimated mortality risk; misalignment is greater for candidates with exceptions. While some exception candidates in Status 1 and 2 do have high estimated mortality risk and legitimately need exceptions, many of these exceptions appear to have been granted to candidates with relatively low medical urgency.
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BibTeX
@article{fatma2026waitlist,
title = {{Waitlist mortality risk (US-CRS score) distribution among status 1 and 2 adult heart transplant candidates with exceptions.}},
author = {Najiya Fatma and Suhani S Patel and Grace R Lyden and Nader Moazami and Brian Wayda and William F Parker and Sommer E Gentry},
journal = {JHLT open},
year = {2026},
month = oct,
doi = {10.1016/j.jhlto.2026.100706},
url = {https://europepmc.org/article/MED/42999889},
note = {CC BY},
}
RIS
TY - JOUR
TI - Waitlist mortality risk (US-CRS score) distribution among status 1 and 2 adult heart transplant candidates with exceptions.
AU - Najiya Fatma
AU - Suhani S Patel
AU - Grace R Lyden
AU - Nader Moazami
AU - Brian Wayda
AU - William F Parker
AU - Sommer E Gentry
PY - 2026
DA - 2026/10/12
JO - JHLT open
DO - 10.1016/j.jhlto.2026.100706
UR - https://europepmc.org/article/MED/42999889
AB - The US-candidate risk score (US-CRS) predicts waitlist mortality among heart transplant candidates using 7 laboratory, cardiovascular, and cardiac device usage variables on a 50-point scale, with higher scores indicating greater mortality risk. We assessed whether US-CRS accurately assigns mortality risk for exception candidates, and whether the alignment of allocation priority with waitlist mortality risk (US-CRS) differs between candidates with and without exceptions. We compared the performance of US-CRS in candidates with and without exceptions using receiver operating curves. We compared US-CRS distributions using the Kolmogorov-Smirnov (KS) test and examined the proportion of candidates below specific score thresholds in each group. We also compared candidates with and without exceptions using Wilcoxon Rank-Sum test for continuous variables and Pearson's Chi-squared test or Fisher exact test for categorical variables. US-CRS is accurate for measuring mortality risk among exception candidates as it is among non-exception candidates. Patients with higher waitlist status had higher median US-CRS. However, the median US-CRS of Status 1 candidates without exceptions (50 [IQR 48-50]) was significantly higher than for candidates with exceptions (45 [36-48]; [ p≤0.05 ]), and similarly for Status 2 (46 [41-49] vs. 42 [32-47]; [ p≤0.05 ]). Notably, 33.13% of Status 1 and 41.28% of Status 2 candidates with exceptions had US-CRS below 40, compared to only 1.84% and 19.20% of candidates without exceptions, respectively. Conversely, among candidates in Status 3 and 4, candidates with exceptions generally had higher US-CRS than candidates without exceptions. Allocation priority under the status system does not align with estimated mortality risk; misalignment is greater for candidates with exceptions. While some exception candidates in Status 1 and 2 do have high estimated mortality risk and legitimately need exceptions, many of these exceptions appear to have been granted to candidates with relatively low medical urgency.
SN - 2950-1334
ER -