The Mesenchymal Stromal Cell Delivery through Cardiopulmonary Bypass in Pediatric Cardiac Surgery study is a prospective, open-label, single-centre, dose-escalation phase 1 trial assessing the safety/feasibility of delivering mesenchymal stromal cells to neonates/infants during cardiac surgery. Outcomes will be compared with historical data from a similar population. We aim to define an optimal control group for use in the Mesenchymal Stromal Cell Delivery through Cardiopulmonary Bypass in Pediatric Cardiac Surgery trial.

Consecutive patients who underwent a two-ventricle repair without aortic arch reconstruction within the first 6 months of life between 2015 and 2020 were studied using the same inclusion/exclusion criteria as the Phase 1 Mesenchymal Stromal Cell Delivery through Cardiopulmonary Bypass in Pediatric Cardiac Surgery trial (n = 169). Patients were allocated into one of three diagnostic groups: ventricular septal defect type, Tetralogy of Fallot type, and transposition of the great arteries type. To determine era effect, patients were analysed in two groups: Group A (2015–2017) and B (2018–2020). In addition to biological markers, three post-operative scoring methods (inotropic and vasoactive-inotropic scores and the Pediatric Risk of Mortality-III) were assessed.

All values for three scoring systems were consistent with complexity of cardiac anomalies. Max inotropic and vasoactive-inotropic scores demonstrated significant differences between all diagnosis groups, confirming high sensitivity. Despite no differences in surgical factors between era groups, we observed lower inotropic and vasoactive-inotropic scores in group B, consistent with improved post-operative course in recent years at our centre.

Our studies confirm max inotropic and vasoactive-inotropic scores as important quantitative measures after neonatal/infant cardiac surgery. Clinical outcomes should be compared within diagnostic groupings. The optimal control group should include only patients from a recent era. This initial study will help to determine the sample size of future efficacy/effectiveness studies.

小儿心脏手术中通过心肺旁路输送间充质基质细胞的研究是一项前瞻性、开放标签、单中心、剂量递增的 1 期试验，评估在心脏手术期间向新生儿/婴儿输送间充质基质细胞的安全性/可行性。结果将与类似人群的历史数据进行比较。我们的目标是确定一个最佳对照组，用于小儿心脏手术试验中通过心肺旁路输送间充质基质细胞。

2015 年至 2020 年期间，使用与小儿心脏手术中通过心肺旁路进行间充质基质细胞递送的 1 期试验相同的纳入/排除标准，对 2015 年至 2020 年期间连续接受两心室修复但未进行主动脉弓重建的患者进行了研究（ n = 169）。患者被分为三个诊断组之一：室间隔缺损型、法洛四联症型和大动脉转位型。为了确定时代效应，将患者分为两组进行分析：A 组（2015-2017 年）和 B 组（2018-2020 年）。除了生物标志物之外，还评估了三种术后评分方法（正性肌力和血管活性-正性肌力评分以及儿科死亡风险-III）。

三个评分系统的所有值均与心脏异常的复杂性一致。最大正性肌力和血管活性-正性肌力评分显示所有诊断组之间存在显着差异，证实了高敏感性。尽管不同时代组之间的手术因素没有差异，但我们观察到 B 组的正性肌力和血管活性-正性肌力评分较低，这与我们中心近年来术后病程的改善一致。

我们的研究证实最大正性肌力和血管活性正性肌力评分是新生儿/婴儿心脏手术后重要的定量指标。临床结果应在诊断分组内进行比较。最佳对照组应仅包括近代患者。这项初步研究将有助于确定未来功效/效果研究的样本量。