Zang Lianru, Gu Kaihao, Ji Xingkai, Zhang Hao, Yan Shengjie, Wu Xiaomei
Center for Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai 200438, China.
Academy for Engineering and Technology, Fudan University, Shanghai 200433, China.
J Cardiovasc Dev Dis. 2022 Sep 22;9(10):319. doi: 10.3390/jcdd9100319.
Pulsed field ablation (PFA) is a promising new ablation modality for the treatment of atrial fibrillation (AF); however, the effect of fiber orientation on the ablation characteristics of PFA in AF treatment is still unclear, which is likely an essential factor in influencing the ablation characteristics. This study constructed an anatomy-based left atrium (LA) model incorporating fiber orientation and selected various electrical conductivity and ablation targets to investigate the effect of anisotropic electrical conductivity (AC), compared with isotropic electrical conductivity (IC), on the ablation characteristics of PFA in AF treatment. The results show that the percentage differences in the size of the surface ablation area between AC and IC are greater than 73.71%; the maximum difference in the size of the ablation isosurface between AC and IC at different locations in the atrial wall is 3.65 mm (-axis), 3.65 mm (-axis), and 4.03 mm (-axis), respectively; and the percentage differences in the size of the ablation volume are greater than 6.9%. Under the condition of the pulse, the amplitude is 1000 V, the total PFA duration is 1 s, and the pulse train interval is 198.4 ms; the differences in the temperature increase between AC and IC in LA are less than 2.46 °C. Hence, this study suggests that in further exploration of the computational study of PFA in AF treatment using the same or similar conditions as those used here (myocardial electrical conductivity, pulse parameters, and electric field intensity damage threshold), to obtain more accurate computational results, it is necessary to adopt AC rather than IC to investigate the size of the surface ablation area, the size of the ablation isosurface, or the size of the ablation volume generated by PFA in LA. Moreover, if only investigating the temperature increase generated by PFA in LA, adopting IC instead of AC for simplifying the model construction process is reasonable.
脉冲场消融（PFA）是一种用于治疗心房颤动（AF）的很有前景的新消融方式；然而，纤维方向对PFA在AF治疗中的消融特性的影响仍不清楚，这可能是影响消融特性的一个关键因素。本研究构建了一个包含纤维方向的基于解剖结构的左心房（LA）模型，并选择了各种电导率和消融靶点，以研究与各向同性电导率（IC）相比，各向异性电导率（AC）对PFA在AF治疗中的消融特性的影响。结果表明，AC和IC之间表面消融区域大小的百分比差异大于73.71%；AC和IC在心房壁不同位置的消融等值面大小的最大差异分别为3.65毫米（-轴）、3.65毫米（-轴）和4.03毫米（-轴）；消融体积大小的百分比差异大于6.9%。在脉冲条件下，振幅为1000伏，PFA总持续时间为1秒，脉冲串间隔为198.4毫秒；LA中AC和IC之间的温度升高差异小于2.46℃。因此，本研究表明，在使用与本文相同或相似的条件（心肌电导率、脉冲参数和电场强度损伤阈值）进一步探索PFA在AF治疗中的计算研究时，为了获得更准确的计算结果，有必要采用AC而不是IC来研究PFA在LA中产生的表面消融区域大小、消融等值面大小或消融体积大小。此外，如果仅研究PFA在LA中产生的温度升高，采用IC而不是AC来简化模型构建过程是合理的。
