Laboratory of Cardiac Physiology Institute of Physiology, Federal Research Center Komi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RAS, Syktyvkar, Russia.
Department of Biomedical Technology, Faculty of Biomedical Engineering, Czech Technical University in Prague, Kladno, Czech Republic.
J Physiol Pharmacol. 2019 Oct;70(5). doi: 10.26402/jpp.2019.5.11. Epub 2020 Jan 30.
In this study we tested a hypothesis that reperfusion ventricular tachyarrhythmias can be modified by direct control of repolarization duration in the perfused myocardium during ischemic exposure. After induction of coronary occlusion, three groups of rats were given agencies affecting repolarization duration tetraethylammonium (TEA) 4 mg/kg, n = 9; pinacidil (Pin) 0.3 mg/kg, n = 11, and saline as placebo (control) n = 10. Unipolar electrograms were recorded from ischemic and perfused areas using an array of 64-electrodes to obtain activation times (ATs), repolarization times (RTs), activation-repolarization intervals (ARIs) and dispersion of repolarization (DOR). During ischemia/reperfusion ARIs in perfused area did not change in the control, significantly increased in the TEA and decreased in the Pin group in respect to baseline, whereas ARIs significantly decreased in the ischemic zone in all groups. DOR also significantly increased in all groups at ischemia and reperfusion. The incidence and total arrhythmia score of reperfusion tachyarrhythmias were significantly greater in TEA group compared to Pin and control groups. In multivariate regression analysis, incidence of VT/VFs and total arrhythmia score were associated with ARIs in the perfused area. Thus, the effect on repolarization durations in the perfused area modified the incidence and severity of the reperfusion-induced ventricular tachyarrhythmias.
在这项研究中，我们检验了一个假设，即在缺血暴露期间通过直接控制灌流心肌的复极持续时间，可以改变再灌注性室性心律失常。在诱导冠状动脉闭塞后，三组大鼠分别给予影响复极持续时间的药物：四乙铵（TEA）4mg/kg（n=9）；吡那地尔（Pin）0.3mg/kg（n=11）和生理盐水作为安慰剂（对照组）（n=10）。使用 64 电极阵列从缺血区和灌流区记录单极电图，以获得激活时间（ATs）、复极时间（RTs）、激活-复极间隔（ARIs）和复极离散度（DOR）。在缺血/再灌注期间，对照组的灌流区 ARI 没有变化，TEA 组显著增加，Pin 组则减少，而所有组的缺血区 ARI 均显著减少。在所有组中，DOR 在缺血和再灌注期间也显著增加。与 Pin 组和对照组相比，TEA 组的再灌注性心动过速的发生率和总心律失常评分显著更高。在多变量回归分析中，VT/VF 的发生率和总心律失常评分与灌流区的 ARI 相关。因此，灌流区复极持续时间的改变影响了再灌注性室性心律失常的发生率和严重程度。
