Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore, 560012, India.
Sci Rep. 2017 Nov 10;7(1):15350. doi: 10.1038/s41598-017-15735-5.
Localized heterogeneities, caused by the regional proliferation of fibroblasts, occur in mammalian hearts because of diseases like myocardial infarction. Such fibroblast clumps can become sources of pathological reentrant activities, e.g., spiral or scroll waves of electrical activation in cardiac tissue. The occurrence of reentry in cardiac tissue with heterogeneities, such as fibroblast clumps, can depend on the frequency at which the medium is paced. Therefore, it is important to study the reentry-initiating potential of such fibroblast clumps at different frequencies of pacing. We investigate the arrhythmogenic effects of fibroblast clumps at high- and low-frequency pacing. We find that reentrant waves are induced in the medium more prominently at high-frequency pacing than with low-frequency pacing. We also study the other factors that affect the potential of fibroblast clumps to induce reentry in cardiac tissue. In particular, we show that the ability of a fibroblast clump to induce reentry depends on the size of the clump, the distribution and percentage of fibroblasts in the clump, and the excitability of the medium. We study the process of reentry in two-dimensional and a three-dimensional mathematical models for cardiac tissue.
局部异质性是由纤维母细胞的区域性增殖引起的，它会出现在哺乳动物心脏中，例如心肌梗死等疾病。这种纤维母细胞团可能成为病理性折返活动的来源，例如心脏组织中的螺旋或卷曲波的电激活。在存在纤维母细胞团等异质性的心脏组织中发生折返，可能取决于介质起搏的频率。因此，研究此类纤维母细胞团在不同起搏频率下的折返起始潜能非常重要。我们研究了高、低频起搏下纤维母细胞团的致心律失常效应。我们发现，与低频起搏相比，高频起搏更能明显地在介质中诱导折返波。我们还研究了其他影响纤维母细胞团在心脏组织中诱导折返潜能的因素。特别是，我们表明纤维母细胞团诱导折返的能力取决于团块的大小、团块中纤维母细胞的分布和百分比以及介质的兴奋性。我们在二维和三维心脏组织数学模型中研究了折返过程。
