The peak-to-end of the T wave in the limb ECG leads reflects total spatial rather than transmural dispersion of ventricular repolarization in an anthopleurin-A model of prolonged QT interval
The peak-to-end of the T wave in the limb ECG leads reflects total spatial rather than transmural dispersion of ventricular repolarization in an anthopleurin-A model of prolonged QT interval
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DOI：
10.1016/j.hrthm.2011.11.046
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发表时间：
2012-05-01
期刊：
影响因子：
5.5
通讯作者：
Aizawa, Yoshifusa
中科院分区：
文献类型：
--
作者：
Izumi, Daisuke;Chinushi, Masaomi;Aizawa, Yoshifusa
背景既往研究表明，T波峰与终的时间间隔（Tp-e）是心室复极跨壁离散度的标志。 目的：研究药物诱导的心室复极过程中（a）局部伪透壁电图（pseudo transmural Tp-e）或肢体导联体表心电图（surface Tp-e）上的Tp-e与（b）心内左心室（LV）复极之间的关系。 QT间期延长。方法使用经anthoppleurin-A处理的开胸犬完整心脏，通过放置在左心室基底前壁、中前壁、心尖前壁、基底外侧、中外侧和心尖外侧左心室壁的针电极记录透壁左心室电图。恢复时间（RT）被计算为每个透壁单极电极的局部复极指数。 结果该模型显示心室复极沿基底轴至心尖轴和沿透壁轴的心率依赖性异质分布较慢。在心率较慢期间，左室心尖部的 RT 比基部长，外侧部的 RT 比前壁长。表面 Tp-e 和总 LV 色散之间存在高度相关性。相反，伪透壁 Tp-e 与透壁 RT 色散相关。心脏中最短的 RT 大致对应于峰值，最长的 RT 与表面心电图上 T 波的末端也是如此。 结论 在药物引起的 QT 间期延长且心室复极心尖基底和前外侧离散度较大的过程中，肢体导联中的 Tp-e 表示整个左心室复极的空间（总）分布。
BACKGROUND Previous studies have showed that the interval between the peak and the end of the T wave (Tp-e) is a marker of transmural dispersion of ventricular repolarization.OBJECTIVE We studied the relationship between (a) the Tp-e on local pseudo transmural electrograms (pseudo transmural Tp-e) or limb leads of body surface electrocardiogram (surface Tp-e) and (b) the intracardiac left ventricular (LV) repolarization during a drug-induced QT-interval prolongation.METHODS Using open-chested canine intact hearts treated by anthopleurin-A, transmural LV electrograms were recorded via needle electrodes placed in the basoanterior, midanterior, apicoanterior, basolateral, midlateral, and apicolateral LV wall. Recovery time (RT) was calculated as an index of local repolarization at each transmural unipolar electrode.RESULTS This model showed slower heart rate-dependent heterogeneous distribution of ventricular repolarization both along the basal to apical axis and along the transmural axis. RT was longer at the LV apex than at the base and longer in the lateral than in the anterior wall during the slower heart rate. A high correlation was found between surface Tp-e and total LV dispersion. In contrast, pseudo transmural Tp-e correlated with transmural RT dispersion. The shortest RT in the heart roughly corresponded to the peak, as did the longest RT with the end of the T wave on the surface electrocardiogram.CONCLUSION During drug-induced QT-interval prolongation with a large apicobasal and anterolateral dispersion of ventricular repolarization, the Tp-e in the limb leads expresses spatial (total) distribution of repolarization in the whole left ventricle.