Validation of three-dimensional conduction models using experimental mapping: are we getting closer?
Validation of three-dimensional conduction models using experimental mapping: are we getting closer?
复制标题
使用实验映射验证三维传导模型：我们离目标更近了吗？
DOI：
10.1016/s0079-6107(98)00008-x
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
Henriquez,CS
中科院分区：
文献类型：
--
作者：
Muzikant,AL;Henriquez,CS
心脏的各向异性材料特性、不规则几何形状和专门的传导系统都影响电激活的三维（3D）传播。有限数量的研究小组已经尝试在3D传导模型中解释这些特征，以更彻底地研究他们在3D实验准备中对心脏电活动的观察。然而，由于缺乏实验的定量验证，这些大尺度传导模型的全部潜力尚未实现。为了使用模型来预测心肌对药物或电刺激的电响应，这种验证是至关重要的。本文介绍了在心室壁3 cm×3 cm×1 cm截面的三维传导模型中起搏激动的定量实验验证。将心外膜和壁内起搏刺激施加在缝合到犬左心室的528通道电极斑块的中心。在起搏期间和起搏后以2 kHz记录单极电描记图。在组织学上和起搏标测中估计电极下方组织内的纤维方向。模拟心外膜电描记图计算表面起搏搏动使用我们的3D bidomain模型的映射组织体积，并结合测得的纤维方向。直接比较了模型和实验中起搏激活产生的细胞外电位和等时图。初步结果表明，我们的3D模型再现定性电图形态和心外膜传导速度的实验数据的关键功能。虽然模型和实验之间的定量一致性是中等的，本文所述的验证方法是评估当今传导模型的预测能力的重要的第一步。
The anisotropic material properties, irregular geometry, and specialized conduction system of the heart all affect the three-dimensional (3D) spread of electrical activation. A limited number of research groups have tried accounting for these features in 3D conduction models to investigate more thoroughly their observations of cardiac electrical activity in 3D experimental preparations. The full potential of these large scale conduction models, however, has not been realized because of a lack of quantitative validation with experiment. Such validation is critical in order to use the models to predict the electrical response of the myocardium to drugs or electrical stimulation. In this paper, a quantitative, experimental validation of paced activation in a 3D conduction model of a 3 cm×3 cm×1 cm section of the ventricular wall is presented. Epicardial and intramural pacing stimuli were applied in the center of a 528 channel electrode plaque sutured to the left ventricle in dogs. Unipolar electrograms were recorded at 2 kHz during and after pacing. Fiber directions within the tissue below the electrodes were estimated histologically and from pace-mapping. Simulated epicardial electrograms were computed for surface paced beats using our 3D bidomain model of the mapped tissue volume incorporating the measured fiber directions. Extracellular potentials and isochronal maps resulting from paced activations in both model and experiment were directly compared. Preliminary results demonstrate that our 3D model reproduces qualitatively such key features of the experimental data as electrogram morphologies and epicardial conduction velocities. Though quantitative agreement between model and experiment was only moderate, the validation approach described herein is an essential first step in assessing the predictive capability of present day conduction models.