ABC | Volume 114, Nº4, April 2020

Original Article Marchese et al. Inspiratory exercise in heart failure Arq Bras Cardiol. 2020; 114(4):656-663 Studies with inspiratory muscle training, performed since 1995 in HF, have focused on demonstrating the improvement in muscle strength and endurance, improvement in functional capacity and quality of life. 6,7 However, the hemodynamic repercussions of the IE remain unclear. Hemodynamic variables When a healthy individual is subjected to a resistive load to exercise, the tendency of the hemodynamic response is to increase SBP, at the same time that the CO will increase and, independently, the components of the formula of this variable. Regarding the intensity of the exercise, there is evidence that the greater the intensity for the same number of repetitions, the greater the increase in HR and blood pressure. 14 In fact, this occurred in the present study because, over the 15 minutes of IE, the highest intensity was responsible for the most significant increases in HR and SBP. Figure 5 – SBP behavior in the IE with the different loads. (Baseline 124.1 ± 27.4 vs 15 min. 130.6 ± 25.9 mmHg, p = 0.001). SBP: systolic blood pressure; IE: inspiratory exercise; mmHg: millimeters of mercury; min.: minutes. (Source: The author). Figure 6 – MAP behavior in the IE with the different loads. (Baseline 85.7 ± 17.9 vs 15 min. 89.2 ± 17.3 mmHg, p = 0.004). MAP: mean arterial pressure; IE: inspiratory exercise; mmHg: millimeters of mercury; min.: minutes. (Source: The author). Figure 7 – Borg results in the IE with different loads. (Basal 0.3 ± 0.9 vs 15 min. 1.1 ± 1.9, p = 0.01). IE: inspiratory exercise; min.: minutes.(Source: The author) Figure 8 – Behavior of the subjective scale of dyspnea in IE with different loads. (Baseline 0.2 ± 0.7 vs 15 min. 0.8 ± 1.5, p = 0.02). IE: inspiratory exercise; min.: minutes. (Source: The author) Figure 9 – Correlation between baseline CO and inspiratory muscle strength, r = 0.45; p = 0.04. CO: cardiac output; l/min: liters per minute; MIP: maximum inspiratory pressure; cm/H 2 O: centimeters of water. 660