Activation patterns in healed experimental myocardial infarction.
Activation patterns in healed experimental myocardial infarction.
复制标题
治愈的实验性心肌梗塞的激活模式。
DOI：
10.1161/01.res.65.6.1698
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发表时间：
1989
影响因子：
20.1
通讯作者：
Spear,JF
中科院分区：
文献类型：
--
作者：
Kadish,A;Balke,CW;Levine,JF;Moore,EN;Spear,JF
通过正交记录的双极电描记图求和形成的向量环的最大振幅已被证明反映了心肌中的激动方向。为了研究向量环的组成部分是否可以提供有关心肌局部区域不同激活方向的信息，我们将“瞬时向量”与实验性心肌梗死的体外制备中的等时激活模式相关联。在研究的13个3 mm x 3 mm区域（来自11个组织）中，至少进行了16次微电极穿刺，部位之间的最小密度为0.8 mm。在七种情况下，其中缺口，不规则，和持续时间延长的电描记图，矢量环在整个时间过程中指向相同的大致方向。在这些制备中，微电极穿刺仅表现出单一的主要激活方向。在六个区域中的五个区域中，存在多方向向量环，两个或更多个单独的局部激活方向对应于向量环的方向。瞬时向量，然后被用来分析在体内的传播模式在10只动物与2-4周龄的实验性心肌梗死。在10只动物的150个位点中，13%包含一个以上的主要局部激活方向。在11个明显异常的部位，在起搏过程中从记录探头周围的4个部位记录了电描记图。当比较四个部位的电描记图特征时，发现电描记图振幅的平均差异为5.9 mV，电描记图持续时间的平均差异为19.1 msec（变异系数，振幅为27%，持续时间为22%）。我们得出结论：1）向量环的瞬时分量准确地代表了不同时刻心脏激动的局部方向。2)实验性心肌梗死的大多数区域尽管存在异常电描记图，但只有一个主要的激活方向。3)然而，在某些区域，可以在相对局部的区域内识别两个主要的局部激活方向。4)实验性心肌梗死的几何激活模式明显依赖于初始激活方向。
The maximum amplitude of vector loops formed by summing orthogonally recorded bipolar electrograms has been shown to reflect the direction of activation in cardiac muscle. To investigate whether components of vector loops could provide information about different activation directions in local areas of myocardium, we correlated "instantaneous vectors" with isochronal activation patterns in an in vitro preparation of experimental myocardial infarction. In thirteen 3 mm x 3 mm regions studied (from 11 tissues), at least 16 microelectrode impalements with a minimum density of 0.8 mm between sites were made. In seven situations in which notched, irregular, and prolonged duration electrograms were present, vector loops pointed in the same general direction throughout their entire time course. In these preparations, microelectrode impalements demonstrated only a single major direction of activation. In five of six areas in which multidirectional vector loops were present, two or more separate local directions of activation corresponded to the directions of the vector loop. Instantaneous vectors were then used to analyze propagation patterns in vivo in 10 animals with 2-4-week-old experimental myocardial infarction. Of 150 sites in the 10 animals, 13% contained more than one major local direction of activation. In 11 markedly abnormal sites, electrograms were recorded during pacing from four sites around the recording probe. When comparing electrogram characteristics from the four sites, a mean difference of 5.9 mV in electrogram amplitude and 19.1 msec in electrogram duration (coefficient of variation, 27% for amplitude and 22% for duration) was found. In only two of the 11 sites was it found that the same number of activation directions occurred from all pacing sites. We conclude: 1) Instantaneous components of vector loops accurately represent local directions of cardiac activation at differing times. 2) Most areas of experimental myocardial infarction have only one major direction of activation despite the presence of abnormal electrograms. 3) In some regions, however, two major local directions of activation can be identified within a relatively local area. 4) Geometric activation patterns in experimental myocardial infarction are markedly dependent on initial activation direction.