Cohen M L, Hoyt R H, Saffitz J E, Corr P B
Cardiovascular Division, Washington University School of Medicine, St. Louis, Missouri 63110.
Am J Physiol. 1989 Aug;257(2 Pt 2):H681-9. doi: 10.1152/ajpheart.1989.257.2.H681.
The detailed activation sequence in myocardium provides information critical to the understanding of the mechanisms of cardiac arrhythmias and the influence of interventions. Despite the pivotal role of activation mapping, the interpretation of isochronic maps and the correlation to detailed tissue morphology may be limited when the interelectrode distances are large with respect to cell dimensions. Additionally, dynamic beat-to-beat variations in the activation pattern or the effect of interventions such as single extra stimuli cannot be assessed adequately without recording from all sites simultaneously. To surmount these limitations, we have fabricated and tested an extracellular recording array consisting of 224 bipolar tungsten wire electrodes with a 350-microns interelectrode distance (140 microns edge-to-edge distance), and used signal processing equipment to record from all electrodes simultaneously at a 2-kHz sample rate. Stimulation can be performed sequentially from 12 different sites at 30 degree angles around the periphery of the recording array. Transarray bipoles can be recorded from any combination of eight radially oriented sites. Activation maps recorded in normal tissue after programmed stimulation and activation maps from an area of fixed anatomic block in the epicardial border zone of infarcted tissue are presented. The results demonstrate a lack of influence of the recording array on the electrophysiological properties of the tissue as verified with transmembrane action potential recordings and sequential extracellular maps. This electrode permits precise assessment of transient details of the activation sequence with unparalleled anatomic resolution.
心肌中的详细激活序列提供了对于理解心律失常机制和干预影响至关重要的信息。尽管激活标测具有关键作用，但当电极间距相对于细胞尺寸较大时，等时图的解读以及与详细组织形态的相关性可能会受到限制。此外，如果不同时从所有位点进行记录，就无法充分评估激活模式的逐搏动态变化或诸如单个额外刺激等干预的效果。为了克服这些限制，我们制作并测试了一种细胞外记录阵列，它由224个双极钨丝电极组成，电极间距为350微米（边缘到边缘距离为140微米），并使用信号处理设备以2千赫兹的采样率同时从所有电极进行记录。刺激可以在记录阵列周边以30度角从12个不同位点依次进行。可以从八个径向排列位点的任何组合记录跨阵列双极信号。展示了在程序刺激后正常组织中记录的激活图以及梗死组织心外膜边界区固定解剖阻滞区域的激活图。结果表明，通过跨膜动作电位记录和连续细胞外图验证，记录阵列对组织的电生理特性没有影响。这种电极能够以无与伦比的解剖分辨率精确评估激活序列的瞬态细节。
