Cooper Joshua M, Patel Rutuke K, Emmi Anthony, Wang Yan, Kirkpatrick James N
Electrophysiology Section, Division of Cardiology, Temple University Health System, Philadelphia, Pennsylvania.
Pacing Clin Electrophysiol. 2014 May;37(5):585-90. doi: 10.1111/pace.12327. Epub 2013 Dec 20.
Biventricular (bi-v) pacing improves congestive heart failure and mortality in patients with left ventricular (LV) dysfunction and electrical dyssynchrony. Effective resynchronization must include an LV pacing contribution to the QRS. Leads 1 and V1 are often exclusively used to verify proper biventricular pacing.
In 40 patients referred to our cardiac resynchronization therapy (CRT) optimization clinic, 12-lead electrocardiograms (ECGs) were obtained during bi-v pacing, right ventricular (RV)-only pacing, LV-only pacing, and a range of atrio-ventricular and ventriculo-ventricular intervals. The presenting bi-v QRS morphology was compared to RV and LV pacing, and RV-only pacing was evaluated for the presence of a Q wave in lead 1 and an R wave in V1.
In 22 patients (55%), RV pacing produced an initial Q wave in lead 1 and/or R wave in V1, mimicking bi-v pacing. In three patients, the presenting bi-v paced ECG looked identical to RV-only pacing. In 28 patients (70%), LV pacing was advanced by a mean of 30 ms after CRT optimization. Using all 12 ECG leads, especially the precordial leads, was necessary to appreciate the QRS changes that occurred when LV pacing meaningfully contributed to electrical activation.
Because of LV pacing latency, some patients require an earlier LV offset to achieve proper resynchronization pacing. Commonly used ECG criteria cannot verify meaningful LV pacing contribution during biventricular pacing because RV-only pacing often creates a Q wave in lead 1 and/or R wave in V1. The full 12-lead ECG during biventricular pacing should be compared with isolated RV and LV pacing to verify that LV pacing is properly contributing to the QRS.
双心室起搏可改善左心室功能不全和电不同步患者的充血性心力衰竭及死亡率。有效的再同步化必须包括左心室起搏对QRS波群的作用。导联1和V1常被单独用于验证双心室起搏是否恰当。
在40例转诊至我们心脏再同步治疗（CRT）优化门诊的患者中，在双心室起搏、仅右心室起搏、仅左心室起搏以及一系列房室和室室间期期间获取12导联心电图（ECG）。将呈现的双心室QRS波形态与右心室和左心室起搏进行比较，并评估仅右心室起搏时导联1中是否存在Q波以及V1中是否存在R波。
22例患者（55%）中，右心室起搏在导联1产生初始Q波和/或在V1产生R波，模拟双心室起搏。3例患者中，呈现的双心室起搏ECG与仅右心室起搏看起来相同。28例患者（70%）中，CRT优化后左心室起搏平均提前30毫秒。使用全部12导联ECG，尤其是胸前导联，对于了解左心室起搏对电激动有显著作用时发生的QRS波变化是必要的。
由于左心室起搏延迟，一些患者需要更早的左心室偏移以实现恰当的再同步化起搏。常用的ECG标准在双心室起搏期间无法验证左心室起搏的显著作用，因为仅右心室起搏常可在导联1产生Q波和/或在V1产生R波。双心室起搏期间的完整12导联ECG应与单独的右心室及左心室起搏进行比较，以验证左心室起搏对QRS波群有恰当作用。
