Gasparini Maurizio, Bocchiardo Mario, Lunati Maurizio, Ravazzi Pier Antonio, Santini Massimo, Zardini Marco, Signorelli Silvia, Passardi Micaela, Klersy Catherine
IRCCS Istituto Clinico Humanitas, Rozzano-MILANO, Italy.
Am Heart J. 2006 Jul;152(1):155.e1-7. doi: 10.1016/j.ahj.2006.04.004.
Little is known on the chronic effects of left ventricular pacing (LV) in heart failure.
Seventy-four patients with LBBB, QRS >130 milliseconds, New York Heart Association class (Bradley DJ, Bradley EA, Braughman KL, et al. Cardiac resynchronization and death from progressive heart failure: a meta-analysis of randomized controlled trials. JAMA 2003;289:730-40.) II, LV ejection fraction (LVEF) <35%, and a class I cardioverter/defibrillator indication were implanted with CRT-D devices and were randomized to either LV or biventricular (BiV) pacing. Response (defined as increases of >5 points increase of LVEF and/or > or = 10% 6-minute walking test [6MWT]) between LV and BiV pacing were compared in an attempt to define the number of patients needed to claim noninferiority of LV pacing. In addition, absolute change in LVEF at 12 months in heart failure patients treated with LV pacing was evaluated. The safety of LV pacing was assessed comparing the total number of ventricular arrhythmia episodes, of hospitalizations, and of deaths between the two pacing modes.
The percentage of responders was comparable for both groups (LV = 75%, BiV = 70%, P = .788); based on the 95% CI of the difference between the groups, 1100 patients would be needed to claim noninferiority of LV pacing (with a 5% CI lower limit). LV pacing induced siginificant LVEF increase (5.2%, P = .002). These results remained unchanged after performing adjustment analyses. There were no differences in the numbers of ventricular arrhythmias, hospitalizations, and death events between the 2 pacing modes.
At 12 months, percentage of responders to LV pacing was similar to BIV pacing. Furthermore, LV pacing achieved a significant increase of ejection fraction. LV pacing is both safe and feasible.
关于左心室起搏（LV）对心力衰竭的长期影响知之甚少。
74例患有左束支传导阻滞、QRS时限>130毫秒、纽约心脏协会心功能分级（Bradley DJ、Bradley EA、Braughman KL等。心脏再同步化与进行性心力衰竭死亡：随机对照试验的荟萃分析。《美国医学会杂志》2003年；289：730 - 40。）为II级、左心室射血分数（LVEF）<35%且有植入I类心脏复律除颤器指征的患者植入心脏再同步化治疗除颤器（CRT - D）设备，并随机分为左心室起搏或双心室（BiV）起搏组。比较左心室起搏和双心室起搏之间的反应（定义为LVEF增加>5个百分点和/或6分钟步行试验[6MWT]增加≥10%），以确定宣称左心室起搏非劣效性所需的患者数量。此外，评估接受左心室起搏治疗的心力衰竭患者12个月时LVEF的绝对变化。通过比较两种起搏模式之间室性心律失常发作总数、住院次数和死亡数来评估左心室起搏的安全性。
两组的反应者百分比相当（左心室起搏组 = 75%，双心室起搏组 = 70%，P = 0.788）；基于两组间差异的95%置信区间，宣称左心室起搏非劣效性需要1100例患者（95%置信区间下限）。左心室起搏导致LVEF显著增加（5.2%，P = 0.002）。进行调整分析后这些结果保持不变。两种起搏模式之间的室性心律失常数量、住院次数和死亡事件数没有差异。
在12个月时，左心室起搏的反应者百分比与双心室起搏相似。此外，左心室起搏使射血分数显著增加。左心室起搏既安全又可行。
