Department of Electrophysiology and Pacing, Centre Médico-Chirurgical Ambroise Paré, Neuilly-sur-Seine, France.
Département de Cardiologie Médicale, Institut Mutualiste Montsouris, Paris, France.
J Cardiovasc Electrophysiol. 2020 Sep;31(9):2405-2414. doi: 10.1111/jce.14629. Epub 2020 Jun 29.
In cardiac resynchronization therapy, pacing the left ventricle (LV) at sites of prolonged electrical delay is associated with better outcomes. We sought to characterize the interrelationships between intrinsic, right-ventricular (RV)-paced, and LV-paced interventricular delays.
The following electrical timings were measured at implantation for all electrodes of the LV quadripolar leads: QLV, interventricular delay in intrinsic rhythm (RVs-LVs), in RV-paced rhythm (RVp-LVs), and in LV-paced rhythm (LVp-RVs). We included 32 patients (78% men, age 72 years, LV ejection fraction 29%, left bundle branch block 84%). QLV and RVs-LVs were correlated (R = .72, p < .0001), as were RVs-LVs and RVp-LVs (R = .27, p = .002) and RVp-LVs and LVp-RVs (R = .60, p < .001). Direction of activation along the four LV lead electrodes was concordant between RVs-LVs and RVp-LVs in only 17 (53%) patients. The latest-activated electrodes in RVs-LVs and RVp-LVs were concordant in 26 (81%) patients, adjacent in 3 (9%) patients, and remote in 3 (9%) patients. Biventricular-paced QRS duration varied by more than 10 ms between the two electrodes in half of the patients with dissimilar latest electrodes. Among the seven echocardiographic nonresponders at 6 months, the programmed electrode was remote from the latest electrode in RVs-LVs in five patients and in RVp-LVs in three patients.
Intrinsic and RV-paced interventricular electrical delays are correlated, but there is substantial heterogeneity between patients. The latest-activated electrode may be different between RVs-LVs and RVp-LVs, and this might have important implications in selecting the optimal LV vector.
心脏再同步治疗中，起搏左心室（LV）的延迟部位与更好的预后相关。我们旨在描述固有、右心室（RV）起搏和 LV 起搏的室间延迟之间的相互关系。
对所有 LV 四极导联的电极均测量以下电时序：QLV、固有节律的室间延迟（RVs-LVs）、RV 起搏节律（RVp-LVs）和 LV 起搏节律（LVp-RVs）。共纳入 32 例患者（78%男性，年龄 72 岁，左室射血分数 29%，左束支传导阻滞 84%）。QLV 与 RVs-LVs 相关（R = .72，p < .0001），RVs-LVs 与 RVp-LVs 相关（R = .27，p = .002），RVp-LVs 与 LVp-RVs 相关（R = .60，p < .001）。仅在 17 例（53%）患者中，RVs-LVs 和 RVp-LVs 之间沿着四个 LV 导联电极的激活方向一致。在 26 例（81%）患者中，RVs-LVs 和 RVp-LVs 中的最晚激活电极一致，在 3 例（9%）患者中相邻，在 3 例（9%）患者中远离。在半数具有不同最晚电极的患者中，双心室起搏 QRS 持续时间在两个电极之间相差超过 10ms。在 6 个月时的 7 例超声心动图无反应者中，5 例患者在 RVs-LVs 中程控电极远离最晚电极，3 例患者在 RVp-LVs 中程控电极远离最晚电极。
固有和 RV 起搏的室间电延迟相关，但患者之间存在很大的异质性。最晚激活的电极可能在 RVs-LVs 和 RVp-LVs 之间不同，这可能对选择最佳的 LV 向量有重要意义。
