Green Harry D, Thomas Glyn, Terry John R
College of Engineering, Mathematics and Physical Sciences, University of ExeterExeter, United Kingdom.
Wellcome Trust Centre for Biomedical Modelling and Analysis, University of ExeterExeter, United Kingdom.
Front Physiol. 2017 Jul 17;8:496. doi: 10.3389/fphys.2017.00496. eCollection 2017.
Atrial fibrillation (AF), the most prevalent cardiac arrhythmia, is commonly initiated by ectopic beats originating from a small myocardial sleeve extending over the pulmonary veins. Pulmonary vein isolation therapy attempts to isolate the pulmonary veins from the left atrium by ablating tissue, commonly by using radiofrequency ablation. During this procedure, the cardiologist records electrical activity using a lasso catheter, and the activation pattern recorded is used as a guide toward which regions to ablate. However, poor contact between electrode and tissue can lead to important regions of electrical activity not being recorded in clinic. We reproduce these signals through the use of a phenomenological model of the cardiac action potential on a cylinder, which we fit to post-AF atrial cells, and model the bipolar electrodes of the lasso catheter by an approximation of the surface potential. The resulting activation pattern is validated by direct comparison with those of clinical recordings. A potential application of the model is to reconstruct the missing electrical activity, minimizing the impact of the information loss on the clinical procedure, and we present results to demonstrate this.
心房颤动(AF)是最常见的心律失常,通常由起源于延伸至肺静脉的一小段心肌袖套的异位搏动引发。肺静脉隔离疗法试图通过消融组织(通常使用射频消融)将肺静脉与左心房隔离开来。在这个过程中,心脏病专家使用套索导管记录电活动,记录的激活模式被用作指导消融哪些区域的依据。然而,电极与组织之间接触不良可能导致临床未记录到电活动的重要区域。我们通过使用圆柱上心脏动作电位的现象学模型来重现这些信号,该模型与房颤后的心房细胞拟合,并通过表面电位近似来模拟套索导管的双极电极。通过与临床记录直接比较来验证所得的激活模式。该模型的一个潜在应用是重建缺失的电活动,将信息丢失对临床程序的影响降至最低,我们展示了相关结果来证明这一点。