Dynamics of intramural scroll waves in three-dimensional continuous myocardium with rotational anisotropy
Dynamics of intramural scroll waves in three-dimensional continuous myocardium with rotational anisotropy
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DOI：
10.1006/jtbi.1999.0965
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发表时间：
1999-08-21
影响因子：
2
通讯作者：
Pertsov, AM
中科院分区：
文献类型：
--
作者：
Berenfeld, O;Pertsov, AM
有人提出，三维心肌中的折返活动可能被组织为围绕称为细丝的奇异线旋转的涡卷波。实验研究表明，细丝往往隐藏在心室壁内，因此，涡卷波不表现出表面的折返活动。在这里，我们分析了这种隐藏的涡卷波是如何受到扭曲的各向异性导致旋转层的心室壁内的肌肉纤维。我们使用了一个心室板（15 x 15 x 15 mm（3））的计算机模型，纤维从内膜到心外膜扭转120度。采用FitzHugh-Nagumo方程模拟动作电位。涡卷波与直线长丝发起在不同深度的板坯和在不同的角度相对于纤维取向。分析表明，与初始条件无关，经过一定的过渡期后，长丝与局部纤维取向一致。细丝的排列由由于纤维旋转引起的细胞耦合的方向变化和边界条件决定。我们的研究结果为多形性室性心动过速和室颤期间壁内折返的发生率高于透壁折返提供了一个机制性解释。(C)北京：科学出版社.
It has been suggested that reentrant activity in three-dimensional cardiac muscle may be organized as a scroll wave rotating around a singularity line called the filament. Experimental studies indicate that filaments are often concealed inside the ventricular wall and consequently, scroll waves do not, manifest reentrant activity on the surface. Here we analyse how such concealed scroll waves are affected by a twisted anisotropy resulting from rotation of layers of muscle fibers inside the ventricular wall. We used a computer model of a ventricular slab (15 x 15 x 15 mm(3)) with a fiber twist of 120 degrees from endocardium to epicardium. The action potential was simulated using FitzHugh-Nagumo equations. Scroll waves with rectilinear filaments were initiated at various depths of the slab and at different angles with respect to fiber orientation. The analysis shows that independent of initial conditions, after a certain transitional period, the filament aligns with the local fiber orientation. The alignment of the filament is determined by the directional variations in cell coupling due to fiber rotation and by boundary conditions. Our findings provide a mechanistic explanation for the prevalence of intramural reentry over transmural reentry during polymorphic ventricular tachycardia and fibrillation. (C) 1999 Academic Press.