In early 2018, a new cardiac allograft allocation scheme based on an individual scoring system considering both the risk of death on the waitlist (Candidate Risk Score) and after heart transplantation (HTx – Transplant Risk Score) was implemented in France.

We aimed to describe the application in clinical practice of the new cardiac allocation scheme.

This retrospective single study included consecutive HTx candidates listed between January 2018 and June 2021 in a French high-volume HTx center. We excluded patients listed for a redo-HTx or for a combined transplantation. Individual candidate and transplant risk scores were calculated at listing and at transplant. For each score, we analyzed the weight of predictive variables in the model, their association with clinical events and their evolution between listing and HTx.

A total of 364 patients were included. Patients were mostly males (77%), their median age at listing was 54 years. During follow-up, 274 patients (74%) were transplanted while 57 patients (15.6%) died or were removed from the waitlist for clinical deterioration. Median duration on waiting list was 19 days (IQR=5–91). Post-transplant survival was 85% at 3-month post-transplant. The detailed analysis of the candidate risk score revealed: (i) an important heterogeneity of the weight of the predictive variables (Fig. 1); (ii) major impact of this score on access to transplantation; (iii) no significant worsening of the score between listing and HTx (P = 0.58). Concerning the Transplant Risk Score, we found that: (i) only a small proportion of patients were considered ineligible to HTx (n=3, 0.8%); (ii) a significant number of patients were contraindicated at least one category of donors (n=45, 12.4%); (iii) the contraindications to two or more categories of donors directly impacted outcomes on the waitlist (increased risk of death, lower chance to get transplanted); (iv) the discrimination of the model to predict post-transplant death was low (AUC=0.65).

This study highlighted new data on the application of risk scores in clinical practice following the implementation of the new cardiac allocation scheme. Both scores had important impact on waitlist outcomes.