Universidade Federal Fluminense, Niterói, RJ, Brasil.
Clínica de Insuficiência Cardíaca, Centro Universitário Serra dos Órgãos, Teresópolis, RJ, Brasil.
Arq Bras Cardiol. 2020 Apr;114(4):656-663. doi: 10.36660/abc.20180375. Epub 2020 May 29.
Background Inspiratory muscle weakness contributes to exercise intolerance and decreased quality of life in patients with heart failure. Studies with inspiratory muscle training show improvement in inspiratory muscle strength, functional capacity and quality of life. However, little is known about the central hemodynamic response (CHR) during inspiratory exercise (IE). Objective To evaluate CHR in a single IE session with different loads (placebo, 30% and 60%) in heart failure. Methods Randomized placebo-controlled clinical trial in patients with heart failure with reduced ejection fraction, functional class II and III. Twenty patients aged 65 ± 11 years completed a single session of inspiratory exercise, in 3 cycles of 15 minutes, with a 1-hour washout, involving loads of 30% (C30), 60% (C60) and placebo, using a linear load resistor (PowerBreathe Light). The noninvasive hemodynamic study was performed by cardiothoracic bioimpedance (Niccomo™ CardioScreen®). Statistical analysis was performed with Student's t-test and Pearson's correlation, and P≤0.05 was considered significant. Results An increase in heart rate (HR) was observed with C30 (64 ± 15 vs 69 ± 15 bpm; p = 0.005) and C60 (67 ± 14 vs 73 ± 14 bpm, p = 0.002). A decrease was observed in systolic volume (SV) with C30 (73 ± 26 vs 64 ± 20 ml; p = 0.004). Cardiac output (CO), on its turn, increased only with C60 (4.6 ± 1.5 vs 5.3 ± 1.7 l/min; p = -0.001). Conclusion When using the 60% load, in a single IE session, changes in CHR were observed. HR and CD increased, as did the Borg scales and subjective sensation of dyspnea. The 30% load reduced the SV. (Arq Bras Cardiol. 2020; 114(4):656-663).
吸气肌力量减弱导致心力衰竭患者运动不耐受和生活质量下降。吸气肌训练研究表明，吸气肌力量、功能能力和生活质量都有所改善。然而，关于吸气运动（IE）期间的中心血液动力学反应（CHR）知之甚少。目的：评估心力衰竭患者单次 IE 时不同负荷（安慰剂、30%和 60%）的 CHR。方法：心力衰竭、射血分数降低、功能分级 II 和 III 的患者进行随机安慰剂对照临床试验。20 名年龄 65±11 岁的患者完成了 1 次吸气运动，3 个周期，每个周期 15 分钟，1 小时洗脱期，使用线性负荷电阻（PowerBreathe Light），涉及 30%（C30）、60%（C60）和安慰剂负荷。非侵入性血液动力学研究通过心肺生物阻抗（Niccomo ™ CardioScreen ® ）进行。采用 Student's t 检验和 Pearson 相关分析进行统计学分析，P≤0.05 为差异有统计学意义。结果：C30（64±15 比 69±15 bpm；p=0.005）和 C60（67±14 比 73±14 bpm，p=0.002）时心率（HR）增加。C30 时收缩容积（SV）下降（73±26 比 64±20 ml；p=0.004）。心输出量（CO）仅在 C60 时增加（4.6±1.5 比 5.3±1.7 l/min；p=-0.001）。结论：在单次 IE 中，使用 60%的负荷时，CHR 发生变化。HR 和 CD 增加，Borg 量表和呼吸困难的主观感觉也增加。30%的负荷降低了 SV。（Arq Bras Cardiol. 2020; 114(4):656-663）。
