Transmural and apicobasal gradients in repolarization contribute to T-wave genesis in human surface ECG
Transmural and apicobasal gradients in repolarization contribute to T-wave genesis in human surface ECG
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DOI：
10.1152/ajpheart.01241.2010
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发表时间：
2011-07-01
影响因子：
4.8
通讯作者：
Hisada, Toshiaki
中科院分区：
文献类型：
--
作者：
Okada, Jun-ichi;Washio, Takumi;Hisada, Toshiaki
Okada J、Washio T、Maehara A、Momomura S、Sugiura S、Hisada T。复极中的跨壁和顶端基底梯度有助于人体表面心电图中 T 波的发生。 Am J Physiol Heart Circ Physiol 301：H200-H208，2011。首次发表于 2011 年 4 月 1 日； doi:10.1152/ajpheart.01241.2010.-表面心电图 T 波形态的细胞基础在临床心脏病学中仍然存在争议。我们使用人体心室和躯干的真实模型检查了动作电位持续时间 (APD) 分布对 T 波形态的影响。我们开发了一个心室有限元模型，由大约 2600 万个元件组成，其中包括传导系统，每个元件均采用心肌细胞的离子流模型实现。该模型被嵌入具有不同器官结构的躯干模型中以获得标准心电图导联。通过将 M 细胞定位在心内膜或心外膜区域，APD 分布在透壁方向发生变化。我们还通过修改离子通道参数引入了 apicobasal 梯度。透壁梯度（M细胞位于心内膜侧）和顶端基底梯度均产生正T波，尽管顶端基底梯度需要非常大的梯度。相比之下，通过透壁梯度获得的T波高度对称，因此不能代表真实的生理状态。只有透壁梯度和中等顶端基底梯度的组合才能在表面心电图中产生生理性 T 波。表面心电图的正T波主要源于心内膜侧具有M细胞的APD的透壁分布，尽管也需要心尖基底梯度才能获得生理波形。
Okada J, Washio T, Maehara A, Momomura S, Sugiura S, Hisada T. Transmural and apicobasal gradients in repolarization contribute to T-wave genesis in human surface ECG. Am J Physiol Heart Circ Physiol 301: H200-H208, 2011. First published April 1, 2011; doi:10.1152/ajpheart.01241.2010.-The cellular basis of the T-wave morphology of surface ECG remains controversial in clinical cardiology. We examined the effect of action potential duration (APD) distribution on T-wave morphology using a realistic model of the human ventricle and torso. We developed a finite-element model of the ventricle consisting of similar to 26 million elements, including the conduction system, each implemented with the ion current model of cardiomyocytes. This model was embedded in a torso model with distinct organ structures to obtain the standard ECG leads. The APD distribution was changed in the transmural direction by locating the M cells in either the endocardial or epicardial region. We also introduced apicobasal gradients by modifying the ion channel parameters. Both the transmural gradient (with M cells on the endocardial side) and the apicobasal gradient produced positive T waves, although a very large gradient was required for the apicobasal gradient. By contrast, T waves obtained with the transmural gradient were highly symmetric and, therefore, did not represent the true physiological state. Only combination of the transmural and the moderate apicobasal gradients produced physiological T waves in surface ECG. Positive T waves in surface ECG mainly originated from the transmural distribution of APD with M cells on the endocardial side, although the apicobasal gradient was also required to attain the physiological waveform.