Moss Arthur J, Hall W Jackson, Cannom David S, Klein Helmut, Brown Mary W, Daubert James P, Estes N A Mark, Foster Elyse, Greenberg Henry, Higgins Steven L, Pfeffer Marc A, Solomon Scott D, Wilber David, Zareba Wojciech
Department of Medicine, University of Rochester Medical Center, Rochester, NY 14642, USA.
N Engl J Med. 2009 Oct 1;361(14):1329-38. doi: 10.1056/NEJMoa0906431. Epub 2009 Sep 1.
This trial was designed to determine whether cardiac-resynchronization therapy (CRT) with biventricular pacing would reduce the risk of death or heart-failure events in patients with mild cardiac symptoms, a reduced ejection fraction, and a wide QRS complex.
During a 4.5-year period, we enrolled and followed 1820 patients with ischemic or nonischemic cardiomyopathy, an ejection fraction of 30% or less, a QRS duration of 130 msec or more, and New York Heart Association class I or II symptoms. Patients were randomly assigned in a 3:2 ratio to receive CRT plus an implantable cardioverter-defibrillator (ICD) (1089 patients) or an ICD alone (731 patients). The primary end point was death from any cause or a nonfatal heart-failure event (whichever came first). Heart-failure events were diagnosed by physicians who were aware of the treatment assignments, but they were adjudicated by a committee that was unaware of assignments.
During an average follow-up of 2.4 years, the primary end point occurred in 187 of 1089 patients in the CRT-ICD group (17.2%) and 185 of 731 patients in the ICD-only group (25.3%) (hazard ratio in the CRT-ICD group, 0.66; 95% confidence interval [CI], 0.52 to 0.84; P=0.001). The benefit did not differ significantly between patients with ischemic cardiomyopathy and those with nonischemic cardiomyopathy. The superiority of CRT was driven by a 41% reduction in the risk of heart-failure events, a finding that was evident primarily in a prespecified subgroup of patients with a QRS duration of 150 msec or more. CRT was associated with a significant reduction in left ventricular volumes and improvement in the ejection fraction. There was no significant difference between the two groups in the overall risk of death, with a 3% annual mortality rate in each treatment group. Serious adverse events were infrequent in the two groups.
CRT combined with ICD decreased the risk of heart-failure events in relatively asymptomatic patients with a low ejection fraction and wide QRS complex. (ClinicalTrials.gov number, NCT00180271.)
本试验旨在确定双心室起搏的心脏再同步治疗（CRT）是否会降低轻度心脏症状、射血分数降低且QRS波群增宽的患者的死亡风险或心力衰竭事件风险。
在4.5年的时间里，我们招募并随访了1820例患有缺血性或非缺血性心肌病、射血分数为30%或更低、QRS时限为130毫秒或更长且纽约心脏协会心功能分级为I级或II级症状的患者。患者按3:2的比例随机分组，分别接受CRT联合植入式心律转复除颤器（ICD）（1089例患者）或单独接受ICD（731例患者）。主要终点是任何原因导致的死亡或非致命性心力衰竭事件（以先发生者为准）。心力衰竭事件由知晓治疗分配情况的医生诊断，但由一个不知晓分配情况的委员会进行裁定。
在平均2.4年的随访期间，CRT-ICD组1089例患者中有187例（17.2%）发生主要终点事件，单纯ICD组731例患者中有185例（25.3%）发生主要终点事件（CRT-ICD组的风险比为0.66；95%置信区间[CI]为0.52至0.84；P = 0.001）。缺血性心肌病患者和非缺血性心肌病患者之间的获益无显著差异。CRT的优势在于心力衰竭事件风险降低了41%，这一发现主要在QRS时限为150毫秒或更长的预先指定亚组患者中明显。CRT与左心室容积显著减小和射血分数改善相关。两组的总体死亡风险无显著差异，每个治疗组的年死亡率均为3%。两组严重不良事件均不常见。
CRT联合ICD降低了射血分数低且QRS波群增宽的相对无症状患者发生心力衰竭事件的风险。（ClinicalTrials.gov编号，NCT00180271。）
