Department of Electrocardiology, Medical University of Lodz, Lodz, Poland.
Cardiol J. 2013;20(4):411-7. doi: 10.5603/CJ.2013.0100.
Device optimization is not routinely performed in patients who underwent cardiac resynchronization therapy (CRT) device implantation. Noninvasive optimization of CRT devices by measurement of cardiac output (CO) can be used as a simple method to assess ventricular systolic performance. The aim of this study was to assess whether optimization of atrioventricular (AV) and interventricular (VV) delay can improve hemodynamic response to CRT and whether this optimization should be performed for each patient individually.
Twenty patients with advanced heart failure New York Heart Association (NYHA) class III/IV, left ventricular ejection fraction ≤ 35% and left bundle branch block (QRS ≥ 120 ms) in sinus rhythm were evaluated from 24 h to 48 h after implantation of a CRT device by means of impedance cardiography (ICG). CO was first measured at each patient's intrinsic rhythm. Patients then underwent adjustments of AV and VV delay from 80 ms to 140 ms and from -60 ms to +60 ms, respectively in 20 ms increment steps and CO at each setting was measured by ICG. Both AV and VV delays were programmed according to the greatest improvement in CO compared to intrinsic rhythm.
There was a statistically signifi cant increase in CO measured at the intrinsic rhythm compared to different AV delay by mean of 21% (3.8 ± 1.0 vs. 4.6 ± 0.1 L/min, p < 0.05). Optimal AV/VV delays with left ventricle-preexcitation or simultaneous biventricular pacing caused additional increased CO from intrinsic rhythm by mean of 32.6% (3.8 ± 1.0 vs. 5.04 ± ± 1.0 L/min, p < 0.05). Optimal AV/VV setting delays also resulted in improved hemodynamic responses compared to VV factory setting delay.
Both AV and VV delay optimization should be performed in clinical practice. Optimal AV delay improved outcome. However, combination of optimized AV/VV delays provided the best hemodynamic response. Optimized AV/VV delays with left ventricle-preexcitation or simultaneous biventricular pacing increased hemodynamic output compared to intrinsic rhythm and VV factory setting delay.
心脏再同步治疗（CRT）装置植入后，通常不会对设备进行优化。通过测量心输出量（CO）对 CRT 设备进行无创优化可作为评估心室收缩性能的简单方法。本研究旨在评估房室（AV）和室间（VV）延迟的优化是否可以改善 CRT 的血液动力学反应，以及是否应针对每个患者单独进行这种优化。
20 例纽约心脏协会（NYHA）心功能 III/IV 级、左心室射血分数≤35%、窦性节律伴左束支传导阻滞（QRS≥120ms）的晚期心力衰竭患者，在 CRT 装置植入后 24 至 48 小时内通过阻抗心动图（ICG）进行评估。首先在每个患者的固有节律下测量 CO。然后，患者的 AV 和 VV 延迟分别从 80ms 调整至 140ms，从-60ms 调整至+60ms，每次调整增加 20ms，并通过 ICG 测量每个设置下的 CO。AV 和 VV 延迟均根据与固有节律相比 CO 的最大改善来编程。
与不同的 AV 延迟相比，固有节律下 CO 的测量值平均增加了 21%（3.8±1.0 比 4.6±0.1L/min，p<0.05）。左心室预激或同时双心室起搏的最佳 AV/VV 延迟导致与固有节律相比 CO 额外增加 32.6%（3.8±1.0 比 5.04±1.0L/min，p<0.05）。与 VV 工厂设置延迟相比，最佳 AV/VV 设置延迟还导致了更好的血液动力学反应。
在临床实践中应同时进行 AV 和 VV 延迟优化。最佳的 AV 延迟可改善预后。然而，优化的 AV/VV 延迟组合可提供最佳的血液动力学反应。与固有节律和 VV 工厂设置延迟相比，左心室预激或同时双心室起搏的优化 AV/VV 延迟可增加血液动力学输出。
