Hren R, Stroink G
Institute of Mathematics, Physics, and Mechanics, University of Ljubljana.
Med Biol Eng Comput. 2001 Jul;39(4):447-54. doi: 10.1007/BF02345367.
Distributions of epicardial potentials, calculated from body surface electrocardiograms (ECGs), were investigated to determine if they could enable detection of multiple sites of ventricular activity. An anatomical model of the human ventricular myocardium was used to simulate activation sequences initiated at nine different ventricular pairs of sites. From these sequences, body surface ECGs were simulated at 352 sites on the torso surface and then used to reconstruct epicardial potentials at 202 sites. The criterion for detection of dual ventricular events was the presence of two distinct primary potential minima in the reconstructed epicardial potentials. The shortest distance between the two events in the right ventricle that resulted in the reconstruction of epicardial potential patterns, featuring two minima, was 27 mm; the distance between the two events in the left ventricle was 23 mm. When Gaussian white noise in the simulated body surface potentials was increased from 3 microV to 15 microV and 50 microV, dual events became more difficult to distinguish. Findings indicate that calculated epicardial potentials provide useful visual information about the presence of multiple ventricular events that is not apparent in features of body surface ECGs, and could be particularly helpful in optimising mapping procedures during difficult or unsuccessful radiofrequency ablations of accessory pathways.
研究了根据体表心电图（ECG）计算的心外膜电位分布，以确定其是否能够检测到心室活动的多个位点。使用人体心室心肌的解剖模型来模拟从九个不同心室位点对起始的激动序列。根据这些序列，在躯干表面的352个位点模拟体表ECG，然后用于重建202个位点的心外膜电位。检测双心室事件的标准是在重建的心外膜电位中存在两个不同的主要电位最小值。导致重建具有两个最小值的心外膜电位模式的右心室中两个事件之间的最短距离为27毫米；左心室中两个事件之间的距离为23毫米。当模拟体表电位中的高斯白噪声从3微伏增加到15微伏和50微伏时，双事件变得更难区分。研究结果表明，计算的心外膜电位提供了关于多个心室事件存在的有用视觉信息，而这些信息在体表ECG特征中并不明显，并且在优化困难或不成功的旁路射频消融过程中的标测程序时可能特别有帮助。
