ABC | Volume 114, Nº4, April 2020

Original Article Marchese et al. Inspiratory exercise in heart failure Arq Bras Cardiol. 2020; 114(4):656-663 More recently, Filusch et al. 24 evaluated 532 patients wi t h conge s t i ve hea r t f a i l u r e u s i ng r i gh t hea r t catheterization and also found a moderate correlation between CO and MIP. The authors state that, as MIP is easily measured in clinical practice, it can become an additional parameter in noninvasive hemodynamic monitoring of disease severity. Meyer et al. 4 were the first to demonstrate that inspiratory muscle strength has an independent prognostic value. They followed up 244 patients with HFREF for 23 months, and the 57 patients (23%) who died over that period had MIP even more reduced than the rest of the sample. Corroborating the findings of Meyer, Frankenstein et al., 5 in a prospective study with 686 patients, showed that MIP can be considered a prognostic value even in patients using β -blockers. Study limitations The sample size made it impossible to assess only the group with inspiratory muscle weakness and, given that the present study had an acute effect, we do not know whether these effects are maintained or attenuated. Further investigations are needed to assess chronic IMT-related CHR. Clinical applicability These data indicate that the hemodynamic response of the IE in its different proposals of resistive load with the linear load resistor could have a potential for safe applicability in non-drug treatment of patients with HF (NYHA II and III), without adverse effects. Conclusions When the 60% load was used in a single session of inspiratory exercise, changes in CHR were observed. Particularly increased heart rate, cardiac output, Borg scale and subjective feeling of dyspnea. The 30% load promoted a decrease in systolic volume. Placebo did not promote significant changes in CHR in the present study and, finally, there was a moderate correlation between cardiac output and inspiratory muscle strength. Author contributions Conception and design of the research: Marchese LD, Chermont S, Pereira SB, Mesquita ET; Acquisition of data: Marchese LD, Chermont S, Warol D, Quintão M; Analysis and interpretation of the data: Marchese LD, Chermont S, Warol D, Oliveira LB, Mesquita ET; Statistical analysis: Marchese LD, Chermont S; Writing of the manuscript: Marchese LD, Warol D; Critical revision of the manuscript for intellectual content: Chermont S, Oliveira LB, Pereira SB, Quintão M, Mesquita ET. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This article is part of the thesis of master submitted by Luana de Decco Marchese, from Universidade Federal Fluminense. 1. 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