Cossú Sergio F
Lehigh Valley Health Network, Allentown, PA, USA.
J Innov Card Rhythm Manag. 2023 Aug 15;14(8):5552-5557. doi: 10.19102/icrm.2023.14085. eCollection 2023 Aug.
Cardiac memory is a common condition occurring after a period of abnormal depolarization, such as with right ventricular apical pacing. With restoration of normal conduction, the T-wave "remembers" the direction of the QRS vector of the previously aberrantly conducted complexes, creating diffusely inverted T-waves on the electrocardiogram. The presence of diffuse T-wave inversions with this phenomenon may be confused with myocardial ischemia and may continue to be present for several weeks after restoration of normal conduction. Here, an interesting electrocardiogram obtained after pacemaker implantation showing the opposite effect, ie, the finding of memory T-waves occurring during pacing after a period of intrinsic atrioventricular nodal conduction, is presented. In this case, the patient had an underlying left bundle branch block, which subsequently normalized as a result of conduction system pacing. The memory T-waves became evident after pacing was performed, suggesting a potential marker for restoration of the normal ventricular activation sequence with left bundle branch pacing and normalization of the baseline intraventricular conduction defect.
心脏记忆是一种在一段异常去极化后出现的常见情况，比如右心室心尖部起搏时。随着正常传导的恢复，T波“记住”了先前异常传导复合波的QRS向量方向，在心电图上产生弥漫性倒置T波。这种现象伴有弥漫性T波倒置可能会与心肌缺血相混淆，并且在正常传导恢复后可能会持续存在数周。在此，展示了一份有趣的起搏器植入后获得的心电图，显示了相反的效应，即在一段时间的固有房室结传导后起搏期间出现记忆T波的发现。在这个病例中，患者存在潜在的左束支传导阻滞，随后由于传导系统起搏而恢复正常。起搏后记忆T波变得明显，提示左束支起搏恢复正常心室激动顺序以及基线室内传导缺陷正常化的一个潜在标志。
