Adamson Philip B, Kleckner Karen J, VanHout Warren L, Srinivasan Sriram, Abraham William T
Department of Internal Medicine, Cardiovascular Disease Section, University of Oklahoma Health Sciences Center, PO Box 26901, 920 SL Young Boulevard, WP3120, Oklahoma City, Okla 73104, USA.
Circulation. 2003 Jul 22;108(3):266-9. doi: 10.1161/01.CIR.0000083368.75831.7A. Epub 2003 Jul 14.
Cardiac resynchronization therapy (CRT) using biventricular pacing improves symptoms and functional capacity in patients with moderate to severe heart failure. The present study examined whether an improvement in ventricular performance from resynchronization therapy changes the autonomic control of heart rate.
Heart rate variability (HRV) was examined in 50 patients implanted with the InSync biventricular pacing system who were randomized to therapy-on (n=25) or therapy-off (n=25). HRV was computed as the standard deviation of the atrial cycle length sensed from the system over 2 months of continuous monitoring. HRV was compared between CRT-on and CRT-off groups. HRV was higher in patients randomized to CRT-on compared with CRT-off (148+/-47 ms for CRT-on versus 118+/-45 ms for CRT-off; P=0.02), despite the lack of difference in mean atrial cycle length (844+/-129 ms for CRT-on versus 851+/-110 ms for CRT-off; P=0.82). Changes in plasma catecholamines were not different between the CRT-on and CRT-off groups from baseline to the 3-month follow-up.
Improvement in ventricular performance from CRT shifts cardiac autonomic balance toward a more favorable profile that is less dependent on sympathetic activation.
使用双心室起搏的心脏再同步治疗（CRT）可改善中重度心力衰竭患者的症状和功能能力。本研究探讨了再同步治疗引起的心室功能改善是否会改变心率的自主控制。
对50例植入InSync双心室起搏系统的患者进行心率变异性（HRV）检测，这些患者被随机分为治疗开启组（n = 25）和治疗关闭组（n = 25）。HRV通过在连续监测的2个月内从系统感知到的心房周期长度的标准差来计算。比较CRT开启组和CRT关闭组的HRV。随机分配到CRT开启组的患者的HRV高于CRT关闭组（CRT开启组为148±47毫秒，CRT关闭组为118±45毫秒；P = 0.02），尽管平均心房周期长度没有差异（CRT开启组为844±129毫秒，CRT关闭组为851±110毫秒；P = 0.82）。从基线到3个月随访，CRT开启组和CRT关闭组的血浆儿茶酚胺变化没有差异。
CRT引起的心室功能改善使心脏自主神经平衡向更有利的状态转变，这种状态对交感神经激活的依赖性较小。
