IEEE Trans Biomed Circuits Syst. 2018 Aug;12(4):791-800. doi: 10.1109/TBCAS.2018.2817027. Epub 2018 May 7.
The rapid progress of invasive therapeutic options for cardiac arrhythmias increases the need for accurate diagnostics. The surface electrocardiogram (ECG) is still the standard of noninvasive diagnostics but lacks atrial signal resolution. By contrast, esophageal electrocardiography (EECG) yields atrial signals of high amplitude and with a high signal-to-noise ratio. Esophageal electrocardiography has become fast and safe, but the mechanical constraints of esophageal measuring catheters and the "random" motion of the catheter inside the subject's esophagus limit the spatial resolution of EECG signals. In this paper, we propose a method to estimate the electrical field projected onto the esophagus with an increased spatial resolution, using commonly available esophageal catheters. In a first step, we estimate the time-varying catheter position, and in a second step, we estimate the projected electrical field with enhanced spatial resolution. The proposed algorithm comprises several consecutive optimization steps, where each intermediate step produces not just a single point estimate, but a cost function over multiple solutions, which reduces the information loss at each processing step. We conclude with examples from a clinical trial, where the fields of cardiac arrhythmias are presented as two-dimensional contour plots.
心脏心律失常的侵袭性治疗方法的快速发展增加了对准确诊断的需求。体表心电图（ECG）仍然是非侵入性诊断的标准，但缺乏心房信号分辨率。相比之下，食管心电图（EECG）产生高振幅和高信噪比的心房信号。食管心电图已经变得快速和安全，但食管测量导管的机械限制和导管在受试者食管内的“随机”运动限制了 EECG 信号的空间分辨率。在本文中，我们提出了一种使用常用食管导管以提高空间分辨率估计投射到食管上的电场的方法。在第一步中，我们估计时变导管位置，在第二步中，我们以增强的空间分辨率估计投影电场。所提出的算法包括几个连续的优化步骤，其中每个中间步骤不仅产生单个点估计，而且产生多个解决方案的成本函数，从而减少了每个处理步骤的信息损失。我们以临床试验中的示例作为结论，其中呈现了心律失常的心脏场作为二维等高线图。
