Medi Caroline, Mond Harry G
Department of Cardiology, The Royal Melbourne Hospital, Melbourne, Australia.
Pacing Clin Electrophysiol. 2009 Feb;32(2):172-6. doi: 10.1111/j.1540-8159.2008.02199.x.
The detrimental effects of right ventricular apical pacing on left ventricular function has driven interest in selective site pacing, predominantly on the right ventricular outflow tract (RVOT) septum. There is currently no information on long-term ventricular lead electrical performance from this site.
A total of 100 patients with ventricular lead placement on the RVOT septum undergoing pacemaker implantation for bradycardia indications were analyzed retrospectively. Lead positioning was confirmed with the use of fluoroscopy. Long-term (1 year) follow-up was obtained in 92 patients. Information on stimulation threshold, R-wave sensing, lead impedance, and lead complications were collected.
Lead performance at the RVOT septal position was stable in the long term. Ventricular electrical parameters were acceptable with stable long-term stimulation thresholds, sensing, and impedance for all lead types. One-year results demonstrated mean stimulation threshold of 0.71 +/- 0.25 V, mean R wave of 12.4 +/- 6.05 mV, and mean impedance values of 520 +/- 127 Omega. There were no cases of high pacing thresholds or inadequate sensing.
This study confirms satisfactory long-term performance with leads placed on the RVOT septum, comparable to traditional pacing sites. It is now time to undertake studies to examine the long-term hemodynamic effects of RVOT septal pacing.
右心室心尖部起搏对左心室功能的有害影响引发了对选择性部位起搏的关注，主要是在右心室流出道（RVOT）间隔处。目前尚无关于该部位心室导线长期电学性能的信息。
回顾性分析了100例因心动过缓适应证在RVOT间隔处植入心室导线并行起搏器植入术的患者。通过荧光透视确认导线位置。92例患者获得了长期（1年）随访。收集了刺激阈值、R波感知、导线阻抗和导线并发症等信息。
长期来看，RVOT间隔位置的导线性能稳定。所有导线类型的心室电学参数均可接受，长期刺激阈值、感知和阻抗均稳定。1年的结果显示，平均刺激阈值为0.71±0.25V，平均R波为12.4±6.05mV，平均阻抗值为520±127Ω。没有高起搏阈值或感知不足的病例。
本研究证实，与传统起搏部位相比，RVOT间隔处放置的导线长期性能令人满意。现在是时候开展研究以检查RVOT间隔起搏的长期血流动力学效应了。
