Division of Cardiovascular Surgery, Toronto General Hospital, University Health Network and the University of Toronto, Toronto, Ontario, Canada.
Biomaterials. 2010 Oct;31(30):7684-94. doi: 10.1016/j.biomaterials.2010.06.048. Epub 2010 Jul 24.
Late after a myocardial infarction (MI), surgical ventricular restoration (SVR) can reduce left ventricular volumes, but an enhanced cardiac patch may be required to restore function. We developed a new, biodegradable patch (modified gelfoam, MGF) consisting of a spongy inner core (gelfoam) to encourage cell engraftment and an outer coating (poly epsilon-caprolactone) to provide sufficient strength to permit ventricular repair. Two weeks after coronary ligation in rats, SVR was performed using one of the following: gelfoam, MGF, MGF patches with hydrogel alone, or with hydrogel and cytokines (stem cell factor, stromal cell-derived factor-1alpha), bone marrow mesenchymal stem cells, or both. Cardiac function and morphology were evaluated by echocardiography, conduction catheterization, magnetic resonance imaging, and histology. Animals whose hearts were repaired with untreated gelfoam died of ventricular rupture. The MGF groups had significantly improved myocardial systolic function vs. MI controls. Enhancement with cytokines and/or cells promoted more alpha-smooth muscle actin-positive cells, more capillaries, greater wall thickness, a more ellipsoid shape, greater fractional shortening, and better-preserved systolic elastance than MGF alone. This combination of the new, reinforced, biodegradable biomaterial and cytokine/cell treatment created a viable tissue after SVR and produced better functional outcomes than un-reinforced gelfoam or MGF alone.
心肌梗死后晚期，外科心室修复（SVR）可减少左心室容积，但可能需要增强的心脏补片来恢复功能。我们开发了一种新的、可生物降解的补片（改良明胶海绵，MGF），由海绵状的内部核心（明胶海绵）组成，以促进细胞移植，并由外部涂层（聚己内酯）组成，以提供足够的强度来允许心室修复。在大鼠冠状动脉结扎后 2 周，使用以下方法之一进行 SVR：明胶海绵、MGF、仅含水凝胶的 MGF 补片、含水凝胶和细胞因子（干细胞因子、基质细胞衍生因子-1alpha）、骨髓间充质干细胞或两者。通过超声心动图、传导导管、磁共振成像和组织学评估心脏功能和形态。用未经处理的明胶海绵修复心脏的动物因心室破裂而死亡。MGF 组的心肌收缩功能明显优于 MI 对照组。与单独使用 MGF 相比，细胞因子和/或细胞增强作用促进了更多的α-平滑肌肌动蛋白阳性细胞、更多的毛细血管、更大的壁厚度、更椭圆的形状、更大的分数缩短和更好的收缩弹性。这种新型、增强型、可生物降解生物材料与细胞因子/细胞治疗的结合在 SVR 后产生了有活力的组织，并产生了比未增强的明胶海绵或单独使用 MGF 更好的功能结果。
