Greater geographic sharing and heart transplantation waitlist outcomes following the 2018 heart allocation policy

OPTN/SRTR 2022 Annual Data Report: Heart

The number of heart transplants in the United States has continued to increase. Since 2011, pediatric heart transplants have increased 31.7% to 494 and adult heart transplants have increased 85.8% to 3,668 in 2022. The numbers of new candidates for pediatric and adult heart transplants have also increased, with 703 new pediatric candidates and 4,446 new adult candidates in 2022. Adult heart transplant rates continue to rise, peaking at 122.5 transplants per 100 patient-years in 2022; however, the pediatric heart transplant rate decreased to its lowest rate in the past decade, 104.2 transplants per 100 patient-years, a decrease of 13.9% from 121 transplants per 100 patient-years in 2011. Despite this, pretransplant mortality among pediatric candidates has decreased by 52.2%, from 20.8 deaths per 100 patient-years in 2011 to 10.0 deaths per 100 patient-years in 2022, but remains excessive for candidates younger than 1 year at 25.7 deaths per 100 patient-years. Among adult candidates, pretransplant mortality declined from 15 deaths per 100 patient-years in 2011 to 8.7 deaths per 100 patient-years in 2022. Since 2011, posttransplant mortality has been stable to slightly better; among recipients who underwent transplant in 2015-2017, the 1-, 3-, and 5-year pediatric survival rates were 93.7%, 89.2%, and 85.0%, respectively, and the adult survival rates were 91.3%, 85.7%, and 80.4%. Donor trends have been favorable, with an increase in the numbers of hearts recovered and growing numbers of hearts procured after circulatory death.

Heart Transplantation

Heart transplantation (HTx) remains the last therapeutic resort for patients with advanced heart failure. The present work is a clinically focused review discussing current issues in heart transplantation. Several factors have been associated with the outcome of HTx, such as ABO and HLA compatibility, graft size, ischemic time, age, infections, and the cause of death, as well as imaging and laboratory tests. In 2018, UNOS changed the organ allocation policy for HTx. The aim of this change was to prioritize patients with a more severe clinical condition resulting in a reduction in mortality of people on the waiting list. Advanced heart failure and resistant angina are among the main indications of HTx, whereas active infection, peripheral vascular disease, malignancies, and increased body mass index (BMI) are important contraindications. The main complications of HTx include graft rejection, graft angiopathy, primary graft failure, infection, neoplasms, and retransplantation. Recent advances in the field of HTx include the first two porcine-to-human xenotransplantations, the inclusion of hepatitis C donors, donation after circulatory death, novel monitoring for acute cellular rejection and antibody-mediated rejection, and advances in donor heart preservation and transportation. Lastly, novel immunosuppression therapies such as daratumumab, belatacept, IL 6 directed therapy, and IgG endopeptidase have shown promising results.