Stem cell therapy offers a breakthrough opportunity for the improvement of ischemic heart diseases. Numerous clinical trials and meta-analyses appear to confirm its positive but variable effects on heart function. Whereas these trials widely differed in design, cell type, source, and doses reinjected, cell injection route and timing, and type of cardiac disease, crucial key factors that may favour the success of cell therapy emerge from the review of their data. Various types of cell have been delivered. Injection of myoblasts does not improve heart function and is often responsible for severe ventricular arrythmia occurrence. Using bone marrow mononuclear cells is a misconception, as they are not stem cells but mainly a mix of various cells of hematopoietic lineages and stromal cells, only containing very low numbers of cells that have stem cell-like features; this likely explain the neutral results or at best the modest improvement in heart function reported after their injection. The true existence of cardiac stem cells now appears to be highly discredited, at least in adults. Mesenchymal stem cells do not repair the damaged myocardial tissue but attenuate post-infarction remodelling and contribute to revascularization of the hibernated zone surrounding the scar. CD34⁺ stem cells - likely issued from pluripotent very small embryonic-like (VSEL) stem cells - emerge as the most convincing cell type, inducing structural and functional repair of the ischemic myocardial area, providing they can be delivered in large amounts via intra-myocardial rather than intra-coronary injection, and preferentially after myocardial infarct rather than chronic heart failure.

中文翻译：

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再生医学治疗获得性心脏病的关键成功因素。

干细胞治疗为改善缺血性心脏病提供了突破性机会。大量临床试验和荟萃分析似乎证实了其对心脏功能的积极但可变的影响。尽管这些试验在设计、细胞类型、来源和再注射剂量、细胞注射途径和时间以及心脏病类型方面存在很大差异，但通过对数据的审查，可以得出可能有利于细胞治疗成功的关键因素。已交付各种类型的细胞。注射成肌细胞不能改善心脏功能，并且常常导致严重室性心律失常的发生。使用骨髓单核细胞是一种误解，因为它们不是干细胞，而是主要是各种造血谱系细胞和基质细胞的混合物，仅含有极少数具有干细胞样特征的细胞；这可能解释了注射后报告的中性结果或至多心脏功能的适度改善。心脏干细胞的真实存在现在似乎受到高度质疑，至少在成年人中是这样。间充质干细胞不会修复受损的心肌组织，但会减弱梗死后的重塑，并有助于疤痕周围冬眠区的血运重建。CD34 ⁺干细胞 - 可能由多能极小胚胎样 (VSEL) 干细胞产生 - 成为最令人信服的细胞类型，诱导缺血心肌区域的结构和功能修复，前提是它们可以通过体内大量递送心肌注射而不是冠状动脉内注射，并且优先在心肌梗塞后而不是慢性心力衰竭后注射。