目前已有许多临床试验证实心脏再同步化治疗(CRT)可以改善心功能,缓解症状,提高生活质量,改善预后。但除CARE-HF以外,其余几项临床试验观察时间较短,因此需要评价随着时间延长CRT的益处能否持续存在或增加或降低。本研究作为CARE-HF的扩展阶段,在研究主体结束后持续8个月,评价C At present, many clinical trials have confirmed that cardiac resynchronization therapy (CRT) can improve cardiac function, relieve symptoms, improve quality of life, and improve prognosis. However, with the exception of CARE-HF, the remaining clinical trials are short-lived and therefore need to assess whether the benefits of CRT persist or increase or decrease over time. This study, as an extended phase of CARE-HF, lasted for 8 months after the end of the study subject and evaluated C