Effects of Strong Electrical Shock on Cardiac Muscle Tissue a
Effects of Strong Electrical Shock on Cardiac Muscle Tissue a
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强电击对心肌组织的影响
DOI：
10.1111/j.1749-6632.1994.tb30444.x
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发表时间：
1994
影响因子：
5.2
通讯作者：
R. O'Neill
中科院分区：
文献类型：
--
作者：
L. Tung;O. Tovar;M. Neunlist;Sandeep K. Jain;R. O'Neill
在临床环境中，故意对心脏施加电击，用于起搏、复律、除颤和消融。施加的电击强度随预期应用而变化，从用于起搏的低值，到首先用于心脏复律然后用于除颤的较高水平，最后到用于电消融的破坏性水平。电流所针对的组织区域在某些情况下可能是高度局部化的（例如，起搏或电消融），或者在其他情况下是全局范围的（例如，除颤）。对于自动植入式心律转复除颤器 (AICD)，电击通常通过位于心室心外膜表面的两个柔性贴片电极传递。2 这种配置值得特别考虑，以免对心脏造成意外伤害。据信，当心脏的大部分受到最小水平的电位梯度时，即可实现成功的除颤。另一方面，电势梯度不可避免地不均匀，在邻近电击电极的区域中电势梯度最高。在高休克水平下，动物实验清楚地表明该区域的组织可能会导致心脏功能受到抑制。尽管心脏损伤的程度不太清楚，但即使在用于心脏复律的较低强度电击后，也可以观察到轻微的心电图变化。 3 在动物研究中观察到的影响包括电生理学改变、心律失常、冠状动脉扩张、收缩力受损、超微结构变化、出血、必需酶耗竭以及最终组织坏死。心脏心肌损伤最直接的指标之一是电生理学，表现为节律异常（心脏骤停、心动过缓、心动过速、传导改变）、心电图形态变化（QRS 波群、ST 段、T 波）或细胞静息电位降低。大量的实验和理论证据表明，高强度电击对心肌的电病理效应源于细胞膜的电穿孔。6 图 1 显示了施加的电击耦合到心脏细胞膜的途径。针对体积导体修改的欧姆定律指出，电阻介质的电势梯度（即每单位长度的电压或电场）与电流密度（每单位交叉电流的电流）成正比。
Electrical shock is deliberately applied to the heart in the clinical setting for pacemaking, cardioversion, defibrillation, and ablation.' The strength of the applied shock varies with the intended application, from low values used for pacemaking, to higher levels used first for cardioversion and then for defibrillation, and ultimately to destructive levels utilized for electrical ablation. The region of tissue targeted by the current may in some cases be highly localized (e.g., with pacemaking or electrical ablation) or in other cases global in extent (e.g., with defibrillation). In the case of automatic implantable cardioverter-defibrillators (AICDs), the shock is commonly delivered through two flexible patch electrodes situated on the epicardial surface of the ventricles.2 This configuration deserves special consideration with respect to unintentional injury to the heart. It is believed that successful defibrillation is achieved when the bulk of the heart is subjected to a minimum level of potential gradient. On the other hand, the potential gradient is unavoidably nonuniform, with the highest level in the region adjacent to the shock electrodes. With high shock levels, animal experiments have clearly shown that tissue in this region can undergo depression in cardiac function. Although the extent of myocardial damage is less clear in h ~ r n a n s , ~ mild electrocardiographic changes can be observed even following the lower intensity shock used for cardioversion.3 Effects observed in animal studies include altered electrophysiology, arrhythmia, coronary artery dilatation, impaired contractility, ultrastructural changes, hemorrhage, depletion of essential enzymes, and ultimately tissue n e c r o s i ~ . ~ , ~ One of the most immediate indices of myocardial injury in the heart is electrophysiological, in the form of rhythm abnormalities (cardiac arrest, bradycardia, tachycardia, altered conduction), morphological changes in the ECG (QRS complex, ST segment, T wave), or decreases in cellular resting potential. There is substantial experimental and theoretical evidence suggesting that the electropathological effects of high-intensity electrical shock on cardiac muscle originate from electroporation of the cell membrane.6 The pathways by which applied electrical shock is coupled to the cardiac cetl membrane are shown in FIGURE 1.Ohm's law modified for volume conductors states that the potential gradient (i.e., voltage per unit length, or electric field) for a resistive medium is proportional to the current density (current per unit cross-
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通过双相矩形波形减少除颤器引起的功能障碍。
DOI：
10.1152/ajpheart.1984.247.5.h792
发表时间：
1984
期刊：
The American journal of physiology
影响因子：
--
作者：
Jones,JL;Jones,RE
通讯作者：
Jones,RE
影响因子：
20.1
作者：
S. Yabe;William M. Smith;J. Daubert;P. Wolf;D. Rollins;R. Ideker
通讯作者：
S. Yabe;William M. Smith;J. Daubert;P. Wolf;D. Rollins;R. Ideker
影响因子：
3.4
作者：
NEEDHAM, D;HOCHMUTH, RM
通讯作者：
HOCHMUTH, RM
高强度电场刺激心肌细胞形成微损伤。
DOI：
10.1152/ajpheart.1987.253.2.h480
发表时间：
1987
期刊：
The American journal of physiology
影响因子：
--
作者：
Jones,JL;Jones,RE;Balasky,G
通讯作者：
Balasky,G