IMPORTANCE Approximately 3500 donated kidneys are discarded in the United States each year, drawing concern from Medicare and advocacy groups. OBJECTIVE To estimate the effects of more aggressive allograft acceptance practices on the donor pool and allograft survival for the population of US wait-listed kidney transplant candidates.

Denatured class I HLA antibodies are common, but the antigens they target should not be considered as unacceptable in most cases, because they negatively impact access to a transplant while predominantly providing negative sensitive crossmatches. The iBeads assay seems to be a valuable alternative to better define unacceptable antigens.

The new French heart allocation system is designed to minimize waitlist mortality and extend the donor pool without a detrimental effect on posttransplant survival. This study was designed to construct a 1‐year posttransplant graft‐loss risk score incorporating recipient and donor characteristics. The study included all adult first single‐organ recipients transplanted between 2010 and 2014 (N = 1776). This population was randomly divided in a 2:1 ratio into derivation and validation cohorts. The association of variables with 1‐year graft loss was determined with a mixed Cox model with center as random effect. The predictors were used to generate a transplant‐risk score (TRS). Donor‐recipient matching was assessed using 2 separate recipient‐ and donor‐risk scores. Factors associated with 1‐year graft loss were recipient age >50 years, valvular cardiomyopathy and congenital heart disease, previous cardiac surgery, diabetes, mechanical ventilation, glomerular filtration rate and bilirubin, donor age >55 years, and donor sex: female. The C‐index of the final model was 0.70. Correlation between observed and predicted graft loss rate was excellent for the overall cohort (r = 0.90). Hearts from high‐risk donors transplanted to low‐risk recipients had similar survival as those from low‐risk donors. The TRS provides an accurate prediction of 1‐year graft‐loss risk and allows optimal donor‐recipient matching.

| INTRODUC TI ONAlthough heart transplantation is the most effective treatment for selected patients with refractory heart failure, access to transplants remains limited by the shortage of heart donors. Currently, in France, the median posttransplant survival is 12 years, with two candidates for one graft and a 1-year waitlist mortality of 11%. 1 In this setting, the new French heart allocation system, implemented in 2018, was designed to minimize waitlist mortality and extend the donor pool while maintaining posttransplant survival. | PRE VI OUS ALLO C ATI ON SYS TEMS IN FR A N CEThe first heart allocation system implemented in France was almost exclusively based on geography with successively local, regional, and national organ sharing, only taking donor and recipient ABO blood types into account. 2 This system was not fair owing to procurement and waitlisting regional disparities in addition to differences in candidate profile from one center to another. In 2004, a novel system was introduced offering hearts first to candidates in immediate life-threatening condition through national priorities. Grafts not allocated through high-urgency (HU) status were then offered to elective candidates according to geography. HU status based on treatment modalities were granted to patients on inotrope infusion or short-term mechanical circulatory support (MCS) (HU1 status), patients on durable MCS with device-related complications (HU2), and patients on uncomplicated biventricular assist device (BiVAD) or total artificial heart (TAH) (HU3). HU status was requested by transplant centers, and HU1 and 2 statuses were granted for periods of 4 and 16 days, respectively. This urgency tier-based allocation system is currently the most widely used heart allocation system in the world. [3][4][5] Graft allocation rules for heart transplantation are necessary because of the shortage of heart donors, resulting in high waitlist mortality. The Agence de la biomédecine is the agency in charge of the organ allocation system in France. Assessment of the 2004 urgency-based allocation system identified challenging limitations. A new system based on a score ranking all candidates was implemented in January 2018. In the revised system, medical urgency is defined according to candidate characteristics rather than the treatment modalities, and an interplay between urgency, donor-recipient matching, and geographic sharing was introduced. In this article, we describe in detail the new allocation system and compare these allocation rules to Eurotransplant and US allocation policies. K E Y W O R D Sethics and public policy, health services and outcomes research, heart transplantation/ cardiology, organ allocation, organ procurement and allocation, waitlist management

Summary Extensively burned patients receive iterative blood transfusions and skin allografts that often lead to HLA sensitization, and potentially impede access to vascularized composite allotransplantation (VCA). In this retrospective, single‐center study, anti‐HLA sensitization was measured by single‐antigen‐flow bead analysis in patients with deep, second‐ and third‐degree burns over ≥40% total body surface area (TBSA). Association of HLA sensitization with blood transfusions, skin allografts, and pregnancies was analyzed by bivariate analysis. The eligibility for transplantation was assessed using calculated panel reactive antibodies (cPRA). Twenty‐nine patients aged 32 ± 14 years, including 11 women, presented with a mean burned TBSA of 54 ± 11%. Fifteen patients received skin allografts, comprising those who received cryopreserved (n = 3) or glycerol‐preserved (n = 7) allografts, or both (n = 5). An average 36 ± 13 packed red blood cell (PRBC) units were transfused per patient. In sera samples collected 38 ± 13 months after the burns, all patients except one presented with anti‐HLA antibodies, of which 13 patients (45%) had complement‐fixing antibodies. Eighteen patients (62%) were considered highly sensitized (cPRA≥85%). Cryopreserved, but not glycerol‐preserved skin allografts, history of pregnancy, and number of PRBC units were associated with HLA sensitization. Extensively burned patients may become highly HLA sensitized during acute care and hence not qualify for VCA. Alternatives to skin allografts might help preserve their later access to VCA.