Hospital Nacional Profesor Alejandro Posadas, Ecuador 1449 10ª "B" (CABA), Buenos Aires, Argentina.
Arrhythmias and Cardiac Pacing Unit, Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Av. Ipiranga, Porto Alegre 6690, RS, Brazil.
J Electrocardiol. 2023 Jul-Aug;79:38-45. doi: 10.1016/j.jelectrocard.2023.03.006. Epub 2023 Mar 11.
The adverse effects of conventional right ventricular (RV) apical pacing prompted the search for more physiological pacing sites, such as selective and nonselective His bundle pacing (HBP), a variant of nonselective HBP (para-Hisian pacing), and mid-septal pacing. However, knowledge of their true benefit on the physiology of ventricular activation, lead stability, and pacing thresholds is limited.
We included 152 consecutive patients (mean age 61 ± 24, 63% men) in this retrospective study. Of these, 137 patients with different bradyarrhythmias underwent active fixation lead implantation at the RV apex (n = 54), para-Hisian region (n = 66), or mid interventricular septum (n = 17). Fifteen patients with ventricular preexcitation due to an accessory pathway not undergoing pacing were included as controls. A 12‑lead ECG was recorded in all patients, and cardiac electrical synchrony was assessed using the Synchromax® cross-correlation cardiac synchrony index (CSI).
QRS duration was prolonged in all pacing sites: from 114 ± 28 to 160 ± 29 (RV apex), from 110 ± 28 to 122 ± 29 (para-Hisian), and from 121 ± 24 to 154 ± 30 (mid interventricular septum). The CSI was significantly improved only in patients undergoing para-Hisian pacing, despite a slight widening of the QRS interval. There was no difference in pacing thresholds and sensed R-wave voltage between pacing sites. Only 1 lead, implanted at the para-Hisian region (1.5%), was dislodged towards the mid septum 48 h after implantation but did not require repositioning.
QRS duration was not associated with changes in CSI, meaning that QRS width does not significantly affect electrical synchrony.
传统右心室（RV）心尖起搏的不良反应促使人们寻找更符合生理的起搏部位，如选择性和非选择性希氏束起搏（HBP）、非选择性 HBP 的一种变体（希氏旁起搏）和中隔部起搏。然而，人们对这些起搏部位在心室激动生理、导线稳定性和起搏阈值方面的真正益处了解有限。
我们回顾性纳入了 152 例连续患者（平均年龄 61±24 岁，63%为男性）。其中，137 例不同缓慢性心律失常患者在 RV 心尖部（n=54）、希氏旁区（n=66）或中隔部（n=17）植入了主动固定导线。15 例因旁道而存在心室预激但未行起搏的患者作为对照。所有患者均记录 12 导联心电图，并使用 Synchromax® 互相关心脏同步指数（CSI）评估心脏电同步性。
所有起搏部位的 QRS 时限均延长：从 RV 心尖部的 114±28 增至 160±29（P<0.001），从希氏旁区的 110±28 增至 122±29（P<0.001），从中隔部的 121±24 增至 154±30（P<0.001）。尽管 QRS 时限略有增宽，但仅在接受希氏旁起搏的患者中 CSI 显著改善。起搏部位之间的起搏阈值和感知 R 波电压无差异。只有 1 例（1.5%）在植入希氏旁区的导线 48 h 后向中隔部移位，但无需重新定位。
QRS 时限与 CSI 变化无关，这意味着 QRS 宽度并不显著影响心脏电同步性。
