米国における心臓移植アロケーションシステム：2018年改訂の成果と今後の課題

抄録

The 2018 revision of the United States heart transplant allocation system introduced a six-tier urgency framework, replacing the prior three-tier classification. This review examines the current allocation structure, donation after circulatory death expansion, multiorgan allocation challenges, geographic sharing policy, and emerging technologies including machine learning risk stratification and xenotransplantation, with comparative insights from Japan.