Lazenby Kevin A, Tolmie Stratton B, Barrett Kenley, White Molly H, Zhang Kevin C, Narang Nikhil, Jasseron Carine, Dorent Richard, Khush Kiran K, Parker William F
Pritzker School of Medicine, University of Chicago, Chicago, IL; Department of Surgery, Washington University in St. Louis, St. Louis, MO.
Pritzker School of Medicine, University of Chicago, Chicago, IL; Department of Medicine, Columbia University, New York, NY.
J Heart Lung Transplant. 2025 Jul 19. doi: 10.1016/j.healun.2025.07.004.
In the US, donor hearts for transplant are currently allocated to the candidates with the highest risk of death on the waiting list, based on a categorical status-based system. The upcoming continuous distribution system provides an opportunity to implement a post-transplant risk score that may help avoid futile transplants.
In this observational study of the Scientific Registry of Transplant Recipients (SRTR), a novel US transplant risk score (US-TRS) was developed and validated using a mixed-effects Cox proportional hazards model. Study participants included adult heart transplant recipients between October 18, 2018, and February 28, 2022, split temporally into training (first 70% of recipients) and test (last 30% of recipients) datasets. We included 8 of 9 French Transplant Risk Score (French-TRS) components plus additional US variables that improved the Akaike Information Criterion (AIC) in the training data. In the test dataset, we assessed US-TRS 1-year post-transplant survival predictions with Uno's concordance index (c-index) and restricted mean survival time (RMST) and compared these results to other post-transplant risk scores, including the French-TRS, the Index for Mortality Prediction After Cardiac Transplantation (IMPACT) score, and recipients' waitlist status at transplantation.
The study cohort consisted of 9,071 heart transplant recipients (mean age 54 [SD 13] years, 72% male), of which 828 (9.1%) died and 29 (0.3%) underwent retransplant within 1 year of transplant. The final US-TRS model included recipient age, bilirubin, estimated glomerular filtration rate (eGFR), albumin, durable left ventricular assist device (LVAD), diabetes, mechanical ventilation, congenital heart disease, donor age, donor sex, and donor-recipient size mismatch. The c-index in the test dataset was 0.671 (95% CI, 0.665-0.687) for the US-TRS model, 0.620 (95% CI, 0.611-0.632) for the French-TRS model, 0.598 for the calculated IMPACT score, and 0.551 (95% CI, 0.540-0.576) for waitlist Status at transplant. US-TRS estimated excellent survival for most recipients, but a minority (17%) of recipients were high risk with an estimated 1-year survival probability of 78% and an average estimated RMST of 311.9 days in the first year.
In this registry-based study of US adult heart transplant recipients, a multivariable risk score outperformed existing models in predicting 1-year post-transplant survival and may be useful for integrating post-transplant survival into the upcoming continuous distribution framework.
在美国，目前移植用的供体心脏是根据基于分类状态的系统分配给等待名单上死亡风险最高的候选人。即将推出的连续分配系统提供了一个机会来实施移植后风险评分，这可能有助于避免无效移植。
在这项对移植受者科学登记处（SRTR）的观察性研究中，使用混合效应Cox比例风险模型开发并验证了一种新的美国移植风险评分（US-TRS）。研究参与者包括2018年10月18日至2022年2月28日期间的成年心脏移植受者，按时间分为训练（前70%的受者）和测试（后30%的受者）数据集。我们纳入了9个法国移植风险评分（French-TRS）组件中的8个以及其他美国变量，这些变量在训练数据中改善了赤池信息准则（AIC）。在测试数据集中，我们使用Uno一致性指数（c指数）和受限平均生存时间（RMST）评估US-TRS移植后1年生存预测，并将这些结果与其他移植后风险评分进行比较，包括French-TRS、心脏移植后死亡率预测指数（IMPACT）评分以及移植时受者在等待名单上的状态。
研究队列包括9071名心脏移植受者（平均年龄54[标准差13]岁，72%为男性），其中828名（9.1%）在移植后1年内死亡，29名（0.3%）在移植后1年内接受了再次移植。最终的US-TRS模型包括受者年龄、胆红素、估计肾小球滤过率（eGFR）、白蛋白、持久性左心室辅助装置（LVAD）、糖尿病、机械通气、先天性心脏病、供体年龄、供体性别以及供受体大小不匹配。US-TRS模型在测试数据集中的c指数为0.671（95%置信区间，0.665-0.687），French-TRS模型为0.620（95%置信区间，0.611-0.632），计算出的IMPACT评分为0.598，移植时等待名单状态的c指数为0.551（95%置信区间，0.540-0.576）。US-TRS估计大多数受者生存率良好，但少数（17%）受者为高风险，估计1年生存概率为78%，第一年平均估计RMST为311.9天。
在这项基于登记处的美国成年心脏移植受者研究中，一个多变量风险评分在预测移植后1年生存方面优于现有模型，可能有助于将移植后生存纳入即将推出的连续分配框架。
