Distribution of excitation frequencies on the epicardial and endocardial surfaces of fibrillating ventricular wall of the sheep heart
Distribution of excitation frequencies on the epicardial and endocardial surfaces of fibrillating ventricular wall of the sheep heart
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DOI：
10.1161/01.res.86.4.408
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发表时间：
2000-03-03
影响因子：
20.1
通讯作者：
Pertsov, AM
中科院分区：
文献类型：
--
作者：
Zaitsev, AV;Berenfeld, O;Pertsov, AM
组织异质性可能在室性心动过速（VT）和室颤（VF）的机制中起重要作用，并可导致兴奋频率的复杂空间分布。在这里，我们使用光学映射和傅立叶分析来确定超过20 000个心室组织的兴奋频率分布。我们的目标是使用这样的分布作为一种工具来量化VF期间的组织程度。通过快速起搏在9个隔离的、冠状动脉灌注的和灌注的绵羊心室板（3 × 3 cm（2））中诱导了14次VT/VF发作。一个双摄像头视频成像系统被用于同时从整个epi-and endoprotein表面的光学记录。在每个像素处确定激发的局部频率，并显示为主频（DF）图。一个典型的DF图由几个（8.2 +/-3.6）离散臂（域）组成，每个域内具有统一的DF。相邻区域的DF比例通常为1：2、3：4或4：5，这表明是区域边界处间歇性文氏样传导阻滞的结果。场域图案相对稳定，可以持续数秒到数分钟。结构域的复杂性、结构域的数量和频率的离散度随着心律失常的发生率而增加。心外膜和心内膜表面的域模式不相关。仅在3次发作中观察到持续的心外膜或心内膜折返。VT/VF期间观察到的频率模式表明，潜在的机制可能是持续的壁内折返源与组织异质性相互作用。
Tissue heterogeneities may play an important role in the mechanism of ventricular tachycardia (VT) and fibrillation (VF) and can lead to a complex spatial distribution of excitation frequencies. Here we used optical mapping and Fourier analysis to determine the distribution of excitation frequencies in >20 000 sites of fibrillating ventricular tissue. Our objective was to use such a distribution as a tool to quantify the degree of organization during VF. Fourteen episodes of VT/VF were induced via rapid pacing in 9 isolated, coronary perfused, and superfused sheep Ventricular slabs (3x3 cm(2)). A dual-camera video-imaging system was used for simultaneous optical recordings from the entire epi-and endocardial surfaces. The local frequencies of excitation were determined at each pixel and displayed as dominant frequency (DF) maps. A typical DF map consisted nf several (8.2+/-3.6) discrete arms (domains) with a uniform DF within each domain. The DFs in adjacent domains were often in 1:2, 3:4, or 4:5 ratios, which was shown to be a result of an intermittent Wenckebach-like conduction block at the domain boundaries. The domain patterns were relatively stable and could persist from several seconds to several minutes. The complexity in the organization of the domains, the number of domains, and the dispersion of frequencies increased with the rate of the arrhythmia. Domain patterns on the epicardial and endocardial surfaces were not correlated. Sustained epicardial or endocardial reentry was observed in only 3 episodes. Observed frequency patterns during VT/VF suggest that the underlying mechanism may be a sustained intramural reentrant source interacting with tissue heterogeneities.