Arteyeva Natalia V, Azarov Jan E
Department of Cardiac Physiology, Institute of Physiology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 50, Pervomayskaya st., Syktyvkar 167982, Russia.
Department of Cardiac Physiology, Institute of Physiology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 50, Pervomayskaya st., Syktyvkar 167982, Russia; Department of Physiology, Medical Institute of Pitirim Sorokin, Syktyvkar State University, 11, Babushkin st., Syktyvkar 167000, Russia.
J Electrocardiol. 2020 May-Jun;60:54-59. doi: 10.1016/j.jelectrocard.2020.03.009. Epub 2020 Mar 20.
An increase in local dispersion of repolarization (DOR) may contribute more to arrhythmogenesis as compared to changes of global DOR. The aim of this simulation study was to find ECG markers of local increase in DOR in conditions where global DOR remains normal.
In the framework of van Oosterom and Oostendorp ECGSIM model, the local DOR was increased in 10 different ventricular locations by (1) action potential duration (APD) shortening/lengthening both on epi- and endocardium, (2) epicardial APD shortening, and (3) endocardial APD shortening. The simulation cases where the increase in local DOR was accompanied by increase in global DOR were excluded from consideration. T-wave parameters were analyzed in the simulated precordial and anatomically ordered limb leads.
The increase in local DOR resulted in increased lead-to‑lead differences in Tpeak and Tend instants in 28 out of 32 simulated scenarios, and in an increased dispersion of Tpeak-Tend interval throughout 12 standard leads in 8 out of 32 simulated scenarios. In all simulations, the global DOR measured as a difference between earliest and latest repolarization times and standard APD deviation was the same.
The local increase in DOR was expressed in increased lead-to‑lead differences in Tpeak and Tend instants between adjacent anatomically ordered standard leads (aVL, I, aVR(-), II, aVF, III, and V1-V6), even if global DOR, Tpeak-Tend interval and Tpeak-Tend dispersion were within a normal range.
与整体复极离散度（DOR）的变化相比，局部复极离散度的增加可能对心律失常的发生起更大作用。本模拟研究的目的是在整体DOR保持正常的情况下，寻找局部DOR增加的心电图标志物。
在范·奥斯特罗姆和奥斯坦多普ECGSIM模型的框架内，通过以下方式在10个不同的心室位置增加局部DOR：（1）缩短/延长心外膜和心内膜的动作电位持续时间（APD），（2）缩短心外膜APD，（3）缩短心内膜APD。排除局部DOR增加伴有整体DOR增加的模拟病例。分析模拟胸前导联和解剖顺序肢体导联中的T波参数。
在32个模拟场景中的28个场景中，局部DOR的增加导致T波峰点（Tpeak）和终点（Tend）时刻的导联间差异增加，在32个模拟场景中的8个场景中，导致12个标准导联中Tpeak - Tend间期离散度增加。在所有模拟中，作为最早和最晚复极时间之差以及标准APD标准差测量的整体DOR保持不变。
即使整体DOR、Tpeak - Tend间期和Tpeak - Tend离散度在正常范围内，局部DOR的增加表现为相邻解剖顺序标准导联（aVL、I、aVR(-)、II、aVF、III和V1 - V6）之间Tpeak和Tend时刻的导联间差异增加。
