Efficacy of noninvasive ventilatory support on exercise tolerance in patients with heart failure: a systematic review

The aim of this study was evaluate the efficacy of noninvasive ventilation (NIV) on improving exercise tolerance of patients with heart failure (HF). A systematic review was performed in PubMed/ MEDLINE, LILACS, Cochrane, CINAHL, Scopus and Web of Science for randomized and quasi-randomized clinical trials, without language and year of publication restrictions. Descriptors were defined as 'heart failure', 'noninvasive ventilation', 'positive-pressure respiration', 'interactive ventilatory support', 'exercise test' in addition to the keywords 'BIPAP', 'CPAP', 'IPAP', 'EPAP', 'NIV' and their Portuguese equivalents. Studies comparing NIV with one or two pressure levels to groups without intervention, other physiotherapy modalities without positive pressure or a sham group were included. Four studies were selected, including HF patients of various etiologies, considering the staging classification of New York Heart Association. Any included work realized the allocation concealment, all studies participants underwent blinding, but only two trials performed assessors blinding. None of the studies have described an intention to treat analysis and did not use appropriate statistical methods. All selected trials assessed functional capacity and in only two, dyspnea was assessed. The intervention protocols of the included trials were heterogeneous, three studies underwent a single intervention with NIV, two immediately before the functional capacity test and another study performed NIV during the exercise evaluation. The last trial held 14 sessions of NIV, with the functional capacity evaluation being performed on day 0, 4, 9 and 14. There is insufficient evidence on the effectiveness of NIV in increasing exercise tolerance.

本研究旨在评估无创通气（noninvasive ventilation, NIV）对改善心力衰竭（heart failure, HF）患者运动耐量的疗效。本研究在PubMed/ MEDLINE、LILACS、Cochrane、CINAHL、Scopus及Web of Science数据库中开展系统综述，检索无语言及发表年份限制的随机与半随机临床试验。检索词设定为“心力衰竭（heart failure）”、“无创通气（noninvasive ventilation）”、“正压呼吸（positive-pressure respiration）”、“交互式通气支持（interactive ventilatory support）”，以及关键词“BIPAP”、“CPAP”、“IPAP”、“EPAP”、“NIV”及其葡萄牙语对应术语。纳入研究需比较NIV单压力水平或双压力水平与无干预组、非正压物理治疗方式组或假干预组。最终纳入4项研究，涵盖不同病因的心力衰竭患者，且均依据纽约心脏协会（New York Heart Association, NYHA）分期标准进行分级。所有纳入研究均实施了分配隐藏，所有研究对象均接受盲法处理，但仅2项试验实施了评价者盲法。无一项研究描述了意向性治疗分析，且未采用恰当的统计方法。所有纳入试验均评估了功能能力，仅2项研究评估了呼吸困难症状。纳入试验的干预方案异质性较高：3项研究仅实施单次NIV干预，其中2项在功能能力测试前即刻开展干预，另有1项在运动评估过程中实施NIV；最后1项试验共开展14次NIV干预，并于第0、4、9、14天分别完成功能能力评估。目前尚无充分证据表明NIV可有效提升心力衰竭患者的运动耐量。