Department of Cardiovascular Surgery, Osaka University Graduate School of Medicine, Japan.
Circ J. 2013;77(4):1063-72. doi: 10.1253/circj.cj-12-0615. Epub 2012 Dec 29.
The implantation of skeletal myoblast (SMB) cell-sheets over the damaged area of a myocardial infarction (MI) has been shown to improve global left ventricular (LV) function through a paracrine effect. However, the regeneration process has not been fully evaluated. We hypothesized that the use of tissue Doppler strain M-mode imaging to assess myocardial layer-specific strain might enable detailed visual evaluation of the regenerative ability of SMBs.
SMBs were cultured on temperature-responsive culture dishes to generate cell-sheets. At 4 weeks after inducing anterior MI, the animals were divided into 2 groups: SMB cell-sheet implantation and sham operation (n=6 in each). A total of 30 cell-sheets (1.5×10(7) cells/sheet) were placed on the epicardium, covering the infarct and border regions. Subendocardial and subepicardial strain values were measured in the infarct, border, and remote regions by tissue Doppler strain analysis. SMB cell-sheet implantation produced the following major effects: progression of LV remodeling was prevented and global LV ejection fraction increased; the subendocardial strain was significantly greater than the subepicardial strain in the treated border region; vascular density in the subendocardium was significantly higher than in the subepicardium in the treated region; the expression of vascular endothelial growth factor was significantly increased.
Tissue Doppler strain analysis allows precise evaluation of the effect of cell-sheet implantation on layer-specific myocardial function.
在心肌梗死（MI）受损区域植入成肌细胞（SMB）细胞片已被证明通过旁分泌作用改善整体左心室（LV）功能。然而，再生过程尚未得到充分评估。我们假设使用组织多普勒应变 M 模式成像来评估心肌层特异性应变可能能够详细评估 SMB 的再生能力。
将 SMB 培养在温度响应培养皿上以生成细胞片。在前 MI 诱导后 4 周，将动物分为 2 组：SMB 细胞片植入和假手术（每组 n=6）。总共放置 30 个细胞片（1.5×10（7）个细胞/片）在心脏外膜上，覆盖梗塞和边界区域。通过组织多普勒应变分析测量梗塞、边界和远程区域的心肌层下和心肌层上应变值。SMB 细胞片植入产生了以下主要效果：阻止 LV 重构的进展并增加整体 LV 射血分数；治疗边界区域的心肌层下应变明显大于心肌层上应变；治疗区域的心肌层下血管密度明显高于心肌层上；血管内皮生长因子的表达明显增加。
组织多普勒应变分析允许精确评估细胞片植入对层特异性心肌功能的影响。
