Department of Cardiothoracic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.
Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.
Pediatr Transplant. 2022 Jun;26(4):e14259. doi: 10.1111/petr.14259. Epub 2022 Mar 8.
Studies have shown that the optimal ischemia time (IT) threshold in pediatric heart transplantation (PHT) is up to 4 h, independent of other donor organ factors. The purpose of this study was to examine the relationship between IT and donor left ventricular ejection fraction (LVEF) and study their impact on PHT outcomes.
This is a retrospective cohort study of PHT (<18 years) identified in UNOS between January 2000 and March 2020. Post-transplantation survival analysis of patients receiving donor hearts with IT<4, 4-6, and >6 h was performed using Kaplan-Meier curves. Cohort was divided according to donor LVEF median value, and survival was analyzed. Cox regression was performed.
Median LVEF was 65% in the study cohort (6669 PHT). Overall, IT>6 h was associated with worse survival compared to <4 h regardless of donor LVEF. For allografts with LVEF < 65%, IT = 4-6 h was associated with worse survival compared with IT < 4 h (p = .006) but had similar survival compared with IT > 6 h (p = .315). For allografts with LVEF ≥ 65%, IT = 4-6 h had similar survival compared with <4 h (p = .175) but improved survival compared with >6 h (p = .003). After adjusting for donor and recipient variables, Cox regression showed that IT = 4-6 h was not associated with increased mortality for LVEF ≥ 65%.
The IT threshold of 4 h does not apply to all allografts. Recipients of hearts with LVEF≥65% can tolerate an IT up to 6 h without any detriment to survival. Routine acceptance of these donor hearts could mitigate longer waiting times and poor donor availability for many candidates.
研究表明，儿科心脏移植（PHT）中最佳缺血时间（IT）阈值可达 4 小时，与其他供体器官因素无关。本研究旨在探讨 IT 与供体左心室射血分数（LVEF）的关系，并研究其对 PHT 结局的影响。
这是一项在 UNOS 中进行的回顾性队列研究，纳入了 2000 年 1 月至 2020 年 3 月期间接受 PHT（<18 岁）的患者。使用 Kaplan-Meier 曲线对接受 IT<4、4-6 和>6 小时供体心脏的患者进行移植后生存分析。根据供体 LVEF 的中位数将队列分为两组，并进行生存分析。进行 Cox 回归分析。
研究队列的 LVEF 中位数为 65%（6669 例 PHT）。总体而言，与 IT<4 小时相比，无论供体 LVEF 如何，IT>6 小时与生存率较差相关。对于 LVEF<65%的同种异体移植物，IT=4-6 小时与 IT<4 小时相比，生存率较差（p=0.006），但与 IT>6 小时相比，生存率相似（p=0.315）。对于 LVEF≥65%的同种异体移植物，IT=4-6 小时与 IT<4 小时相比，生存率相似（p=0.175），但与 IT>6 小时相比，生存率提高（p=0.003）。在校正供体和受体变量后，Cox 回归显示 IT=4-6 小时与 LVEF≥65%的患者死亡率增加无关。
4 小时的 IT 阈值并不适用于所有同种异体移植物。LVEF≥65%的心脏受体可以耐受长达 6 小时的 IT，而不会对生存率造成任何影响。常规接受这些供体心脏可以减轻许多候选者的等待时间延长和供体可用性差的问题。
