Beltran-Molina Ferney A, Cruz-Salazar Emeterio, Requena-Carrion Jesus
Annu Int Conf IEEE Eng Med Biol Soc. 2015 Aug;2015:2223-6. doi: 10.1109/EMBC.2015.7318833.
Body-surface dominant frequency (DF) mapping has been proposed as a technique for non-invasively identifying high-frequency cardiac sources during fibrillation. However, previous studies indicate that volume conduction could distort the spectrum of body-surface cardiac signals and hence, affect body-surface DF maps. In this study, we analyze the effects of volume conduction on the spectrum of cardiac signals in a realistic computer model of the canine ventricles. We simulate complex cardiac dynamics on the ventricular model and analyze the dependence of the bandwidth (BW) of simulated unipolar cardiac signals on the spatial resolution of the corresponding unipolar electrode, which we quantify with the lead equivalent volume (LEV). Our analysis shows that the BW decreases for increasing LEV values and saturates for high LEV values. Our results also indicate that the LEV saturation value is low for low degrees of spatiotemporal correlation. We conclude that the spectral effects of volume conduction might limit our ability to accurately identify high-frequency sources in body-surface DF maps during cardiac fibrillation.
体表主导频率（DF）映射已被提议作为一种在颤动期间非侵入性识别高频心脏源的技术。然而，先前的研究表明，容积传导可能会扭曲体表心脏信号的频谱，从而影响体表DF图。在本研究中，我们在犬心室的真实计算机模型中分析容积传导对心脏信号频谱的影响。我们在心室模型上模拟复杂的心脏动力学，并分析模拟单极心脏信号的带宽（BW）对相应单极电极空间分辨率的依赖性，我们用等效容积导联（LEV）对其进行量化。我们的分析表明，随着LEV值的增加，BW减小，并且在高LEV值时达到饱和。我们的结果还表明，对于低程度的时空相关性，LEV饱和值较低。我们得出结论，容积传导的频谱效应可能会限制我们在心脏颤动期间准确识别体表DF图中高频源的能力。
