Cellular basis for the electrocardiographic J wave
Cellular basis for the electrocardiographic J wave
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DOI：
10.1161/01.cir.93.2.372
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发表时间：
1996-01-15
期刊：
影响因子：
37.8
通讯作者：
Antzelevitch, C
中科院分区：
文献类型：
--
作者：
Yan, GX;Antzelevitch, C
背景：J波是心电图中出现的一种偏转，在QRS波后出现一个迟发的δ波或一个小的继发性R波（R '）。J波也被称为奥斯本波，已经在动物和人类的ECG中观察了四十多年，但对其表现的机制知之甚少。本研究调查的J波使用一个孤立的动脉灌注制剂组成的一个楔形犬右或左ventriculo.Methods和结果的细胞基础，12导联心电图最初记录在体内。在右心室或左心室楔的隔离和动脉灌注后，用三个浮动微电极同时记录心外膜、M区和内膜跨壁部位的跨膜动作电位。同时记录透壁ECG。在20只成年犬中的17只中，在ECG的R-ST连接处观察到J波，通常在导联II、III、aVR和aVF以及中间至外侧心前区导联。记录的跨楔的透壁ECG中的J波与心外膜而非心内膜中存在显著的动作电位切迹密切相关。发现J波的形状和振幅取决于（1）动作电位切迹振幅的跨壁分布，（2）壁内不同部位动作电位早期相（切迹宽度）的相对时间过程，（3）激活顺序，以及（3）跨壁传导时间。心外膜动作电位切迹的振幅与在改变心电图J波外观的干预期间记录的J波振幅之间存在高度显著的相关性，包括低温、过早刺激和4-氨基吡啶阻断瞬时外向电流，从心内膜到心外膜的心室激动。心外膜最后激活也是J波出现的重要前提。这个序列允许建立一个电压梯度的早期阶段的动作电位激活领带后，QRS）是completed.Conclusions我们的研究结果提供了第一个直接的证据支持的假设，即不均匀分布的瞬态外向电流介导的尖峰和圆顶形态的动作电位跨心室壁的基础上的心电图J波的表现。心外膜而非心内膜存在显著的动作电位切迹，可提供电压梯度，表现为J（奥斯本）波或EGG J点升高。
Background The J wave is a deflection that appears in the ECG as a late delta wave following the QRS or as a small secondary R wave (R'). Also referred to as an Osborn wave, the J wave has been observed in the ECG of animals and humans for more than four decades, yet the mechanism underlying its manifestation is poorly understood. The present study investigates the cellular basis for the J wave using an isolated arterially perfused preparation consisting of a wedge of canine right or left ventricle.Methods and Results A 12-lead ECG was initially recorded in vivo. After isolation and arterial perfusion of the right or left ventricular wedge, transmembrane action potentials were simultaneously recorded from epicardial, M region, and endocardial transmural sites with three floating microelectrodes. A transmural ECG was recorded concurrently. A J wave was observed at the R-ST junction of the ECG in 17 of 20 adult dogs, usually in leads II, III, aVR, and aVF and the mid to lateral precordial leads. The J wave in the transmural ECG recorded across the wedge was closely associated with the presence of a prominent action potential notch in epicardium but not endocardium. The shape and amplitude of the J wave were found to depend on (1) the transmural distribution of the action potential notch amplitude, (2) the relative time course of the early phases of the action potential (width of notch) at different sites within the wall, (3) sequence of activation, and (3) conduction time across the wall. A highly significant correlation was demonstrated between the amplitude of the epicardial action potential notch and the amplitude of the J wave recorded during interventions that alter the appearance of the electrocardiographic J wave, including hypothermia, premature stimulation, and block of the transient outward current by 4-aminopyridine, Ventricular activation from endocardium to epicardium. with epicardium activated last, was also an important prerequisite for the appearance of the J wave. This sequence permits the establishment of a voltage gradient of the early phases of the action potential after activation tie, the QRS) is complete.Conclusions Our results provide the first direct evidence in support of the hypothesis that heterogeneous distribution of a transient outward current-mediated spike-and-dome morphology of the action potential across the ventricular wall underlies the manifestation of the electrocardiographic J wave. The presence of a prominent action potential notch in epicardium but not endocardium is shown to provide a voltage gradient that manifests as a J (Osburn) wave or elevated J-point in the EGG.