Institute of Cardiology, University of Bologna, Azienda Ospedaliera S. Orsola-Malpighi, Bologna, Italy.
Am Heart J. 2010 Jun;159(6):1052-1058.e1. doi: 10.1016/j.ahj.2010.03.008.
Biventricular (BiV) stimulation is the preferred means of delivering cardiac resynchronization therapy (CRT), although left ventricular (LV)-only stimulation might be as safe and effective. B-LEFT HF is a prospective, multicenter, randomized, double-blind study aimed to examine whether LV-only is noninferior to BiV pacing regarding clinical and echocardiographic responses.
B-LEFT HF randomly assigned 176 CRT-D recipients, in New York Heart Association class III or IV, with an LV ejection fraction < or =35% and QRS > or =130 milliseconds, to a BiV (n = 90) versus LV (n = 86) stimulation group. Clinical status and echocardiograms were analyzed at baseline and 6 months after CRT-D implant to test the noninferiority of LV-only compared with BiV stimulation.
The proportion of responders was in line with current literature on CRT, with improvement in heart failure composite score in 76.2% and 74.7% of patients in BiV and LV groups, respectively. Comparing LV versus BiV pacing, the small differences in response rates and corresponding 95% CI indicated that LV pacing was noninferior to BiV pacing for a series of response criteria (combination of improvement in New York Heart Association and reverse remodeling, improvement in heart failure composite score, reduction in LV end-systolic volume of at least 10%), both at intention-to-treat and at per-protocol analysis.
Left ventricular-only pacing is noninferior to BiV pacing in a 6-month follow-up with regard to clinical and echocardiographic responses. Left ventricular pacing may be considered as a clinical alternative option to BiV pacing.
双心室（BiV）刺激是提供心脏再同步治疗（CRT）的首选方法，尽管仅左心室（LV）刺激可能同样安全有效。B-LEFT HF 是一项前瞻性、多中心、随机、双盲研究，旨在研究仅 LV 刺激在临床和超声心动图反应方面是否不劣于 BiV 起搏。
B-LEFT HF 将 176 名 CRT-D 接受者随机分为 BiV（n=90）和 LV（n=86）刺激组，这些患者在纽约心脏协会（NYHA）III 或 IV 级，LV 射血分数<或=35%，QRS>或=130 毫秒。在 CRT-D 植入后 6 个月，分析临床状况和超声心动图，以检验与 BiV 刺激相比，仅 LV 刺激的非劣效性。
应答者的比例与 CRT 的当前文献一致，BiV 和 LV 组患者的心力衰竭综合评分分别改善了 76.2%和 74.7%。与 BiV 起搏相比，LV 起搏的应答率和相应的 95%CI 之间的微小差异表明，LV 起搏在一系列应答标准（纽约心脏协会和逆向重构的改善、心力衰竭综合评分的改善、LV 收缩末期容积至少减少 10%）方面不劣于 BiV 起搏，无论是意向治疗还是方案分析。
在 6 个月的随访中，LV 仅起搏在临床和超声心动图反应方面不劣于 BiV 起搏。LV 起搏可能被视为 BiV 起搏的一种临床替代选择。
