Oswald Hanno, Asbach Stefan, Köbe Julia, Weglage Heinrich, Schulte-Pitzke Bernfried, Brachmann Johannes
Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany.
Heart Center, University of Freiburg, Germany.
Pacing Clin Electrophysiol. 2015 Aug;38(8):942-50. doi: 10.1111/pace.12664. Epub 2015 Jun 12.
Cardiac resynchronization therapy (CRT) relies on sufficient left ventricular (LV) pacing with safety margin to phrenic nerve stimulation (PNS). Previous studies introduced LV vector reprogramming in bipolar coronary sinus leads to optimize LV pacing and avoid PNS. We investigated the efficacy and reliability of quadripolar leads in CRT.
The EffaceQ study enrolled 344 patients with de novo CRT implantation with a quadripolar LV lead in an observational, prospective multicenter study. The study was powered to demonstrate that in at least 90% of patients with an implanted quadripolar LV lead, a viable LV pacing configuration (LVPC) is available (primary end point: LV pacing threshold ≤2.5 V/0.5 ms, sufficient PNS margin).
Quadripolar leads were successfully implanted in 96% of patients. A total of 278 of 299 (93.0%) patients with complete data met the criteria for viable LVPC. With the use of traditional LVPCs, a viable LVPC would have been available (268 of 299 patients; P = 0.002) in significantly fewer patients (89.6%). In any LVPC, PNS was inducible in 65.0% of patients and 22.6% of patients reported PNS during ambulatory 3-month follow-up. LVPC reprogramming was performed in 49.8% of patients. PNS inducibility decreased from distal to proximal electrodes, whereas LV pacing thresholds increased from distal to proximal. At prehospital discharge, 5.9 ± 2.8 viable LVPCs were observed, stable during follow-up. The quadripolar electrode offered significantly more LVPC for LV optimization and PNS avoidance.
Quadripolar LV leads yield high numbers of patients with viable LVPCs and alternatives for noninvasive repositioning of LV pacing.
心脏再同步治疗（CRT）依赖于对左心室（LV）进行足够的起搏，并留有安全余量以避免膈神经刺激（PNS）。既往研究提出在双极冠状窦导联中进行左心室向量重编程，以优化左心室起搏并避免膈神经刺激。我们研究了四极导联在CRT中的疗效和可靠性。
EffaceQ研究纳入了344例初次植入CRT且使用四极左心室导联的患者，这是一项观察性、前瞻性多中心研究。该研究旨在证明，在至少90%植入四极左心室导联的患者中，可获得可行的左心室起搏配置（LVPC）（主要终点：左心室起搏阈值≤2.5V/0.5ms，有足够的膈神经刺激余量）。
96%的患者成功植入了四极导联。在299例有完整数据的患者中，共有278例（93.0%）符合可行LVPC的标准。使用传统LVPC时，可行LVPC的患者数量会显著减少（299例患者中的268例；P=0.002）（89.6%）。在任何LVPC中，可以诱发出膈神经刺激的患者占65.0%，22.6%的患者在3个月的动态随访中报告有膈神经刺激。49.8%的患者进行了LVPC重编程。从远端电极到近端电极，膈神经刺激的可诱导性降低，而左心室起搏阈值从远端到近端升高。在出院前，观察到5.9±2.8种可行的LVPC，随访期间保持稳定。四极电极提供了更多用于左心室优化和避免膈神经刺激的LVPC。
四极左心室导联可使大量患者获得可行的LVPC，并为左心室起搏的非侵入性重新定位提供了更多选择。
