Lau Michael, Hu Betty, Werneth Randy, Sherman Marshall, Oral Hakan, Morady Fred, Krysl Petr
Medtronic Ablation Frontiers, Carlsbad, CA, USA.
Pacing Clin Electrophysiol. 2010 Sep;33(9):1089-100. doi: 10.1111/j.1540-8159.2010.02801.x.
The development of a unique radiofrequency (RF) cardiac ablation system, for the treatment of cardiac arrhythmias, is driven by the clinical need to safely create large uniform lesions while controlling lesion depth. Computational analysis of a finite element model of a three-dimensional, multielectrode, cardiac ablation catheter, powered by a temperature-controlled, multiphase, duty-cycled RF generator, is presented.
The computational model for each of the five operating modes offered by the generator is compared to independent tissue temperature measurements taken during in vitro ablation experiments performed on bovine myocardium.
The results of the model agree with experimental temperature measurements very closely-the average values for mean error, root mean square difference, and correlation coefficient were 1.9°C, 13.3%, and 0.97, respectively. Lesions are shown to be contiguous and no significant edge effects are observed.
Both the in vitro and computational model results demonstrate that lesion depth decreases consistently as the bipolar-to-unipolar ratio increases-suggesting a clinical application to potentially control lesion depth with higher fidelity than is currently available. The effect of variable design parameters and clinical conditions on RF ablation can now be expeditiously studied with this validated model.
一种用于治疗心律失常的独特射频（RF）心脏消融系统的开发，是由在控制病变深度的同时安全创建大的均匀病变的临床需求驱动的。本文介绍了一种由温度控制、多相、占空比调制的射频发生器供电的三维多电极心脏消融导管有限元模型的计算分析。
将发生器提供的五种操作模式中每种模式的计算模型与在牛心肌上进行的体外消融实验期间进行的独立组织温度测量进行比较。
模型结果与实验温度测量结果非常吻合——平均误差、均方根差和相关系数的平均值分别为1.9°C、13.3%和0.97。病变显示为连续的，未观察到明显的边缘效应。
体外和计算模型结果均表明，随着双极与单极比率的增加，病变深度持续减小——这表明在临床应用中可能比目前更精确地控制病变深度。现在可以使用这个经过验证的模型快速研究可变设计参数和临床条件对射频消融的影响。
