Department of Cardiology, Aberdeen Royal Infirmary/University of Aberdeen, Aberdeen AB25 2ZN, UK
Department of Cardiology, Aberdeen Royal Infirmary/University of Aberdeen, Aberdeen AB25 2ZN, UK.
Europace. 2015 Jan;17(1):94-100. doi: 10.1093/europace/euu259. Epub 2014 Oct 30.
To compare the effects on left ventricular (LV) function of right ventricular (RV) septal pacing vs. cardiac resynchronization therapy (CRT) in patients with an indication for the latter. Cardiac resynchronization therapy is an effective therapy in patients with drug-refractory heart failure. Despite advances in implantation techniques, LV lead placement can be impossible in up to 10% of cases. We, therefore, assessed the effects of RV septal pacing from mid septum (RVmIVS) and outflow tract (RVOT) on cardiac performance, in comparison with CRT.
Twenty-two patients scheduled for CRT underwent dual-chamber temporary pacing. The ventricular lead was placed at the RV apex (RVA), RVmIVS, and RVOT in random order. Comprehensive echocardiography was performed in a baseline AAI mode and then at each RV position in dual chamber pacemaker function (D pacing, D sensing, D dual responses) mode and repeated on the next day following CRT implantation. Right ventricular apex pacing did not change any of the assessed echocardiography parameters. Both RVmIVS and RVOT pacing increased LV ejection fraction (EF): 29 ± 7% at baseline vs. 32 ± 6% (P = 0.02) and 32 ± 5% (P = 0.04) with RVmIVS and RVOT pacing, respectively. Similarly, the dyssynchrony index (Ts-SD) decreased: 50 ± 19 ms at baseline vs. 39 ± 17 ms (P = 0.04) and 37 ± 17 ms (P = 0.006) with RVmIVS and RVOT pacing, respectively. Cardiac resynchronization therapy further improved LVEF and Ts-SD to 36 ± 7% and 34 ± 15 ms, respectively, however, only LVEF was significantly higher compared with RVmIVS and RVOT pacing (P = 0.03 and P = 0.01 respectively). There were no significant differences in either LVEF or Ts-SD between RVmIVS and RVOT.
Right ventricular septal pacing from mid septum or RVOT pacing improves LVEF and LV synchrony in CRT candidates. Further improvement in LVEF was achieved by CRT, which remains the 'gold standard' therapy in these patients. However, RV septal pacing is worthy of further study as an alternative strategy when LV lead implantation fails.
比较右心室（RV）间隔起搏与心脏再同步治疗（CRT）对有适应证的患者左心室（LV）功能的影响。心脏再同步治疗是药物难治性心力衰竭患者的有效治疗方法。尽管植入技术有所进步，但在多达 10%的情况下，LV 导联的放置可能是不可能的。因此，我们评估了从中隔（RVmIVS）和流出道（RVOT）进行 RV 间隔起搏对心脏性能的影响，并与 CRT 进行了比较。
22 名计划行 CRT 的患者接受了双腔临时起搏。心室导联以随机顺序放置在 RV 心尖（RVA）、RVmIVS 和 RVOT。在基础 AAI 模式下进行全面超声心动图检查，然后在每个 RV 位置的双腔起搏器功能（D 起搏、D 感知、D 双反应）模式下重复，并在 CRT 植入后第二天重复。RV 心尖起搏不会改变任何评估的超声心动图参数。RVmIVS 和 RVOT 起搏均增加了 LV 射血分数（EF）：基础时为 29 ± 7%，分别为 32 ± 6%（P = 0.02）和 32 ± 5%（P = 0.04）。同样，离散时间指数（Ts-SD）降低：基础时为 50 ± 19 ms，分别为 39 ± 17 ms（P = 0.04）和 37 ± 17 ms（P = 0.006）。心脏再同步治疗进一步将 LVEF 和 Ts-SD 改善至 36 ± 7%和 34 ± 15 ms，但仅 LVEF 与 RVmIVS 和 RVOT 起搏相比显著更高（P = 0.03 和 P = 0.01）。RVmIVS 和 RVOT 之间的 LVEF 或 Ts-SD 均无显著差异。
从中隔或 RVOT 进行 RV 间隔起搏可改善 CRT 候选者的 LVEF 和 LV 同步性。心脏再同步治疗进一步改善了 LVEF，仍然是这些患者的“金标准”治疗方法。然而，当 LV 导联植入失败时，RV 间隔起搏值得进一步研究作为替代策略。
