Effects of Addition of Inspiratory Muscle Training to Exercise-Based Cardiac Rehabilitation on Inspiratory Muscle Strength, Peak Oxygen Consumption, and Selected Hemodynamics in Chronic Heart Failure.

Abstract

Evidence supports the clinical benefits of isolated inspiratory muscle training (IMT) in patients with chronic heart failure (CHF); however, the rationale of IMT in combination with exercise training in cardiac rehabilitation settings for CHF has yet to be confirmed. This study aimed to assess the effect of the addition of IMT in combination with aerobic/resistance training (AT/RT) on maximal inspiratory pressure (PImax), peak oxygen consumption (VO2peak), selected hemodynamic variables, and health-related quality of life (HRQoL) compared to sham-IMT combined with AT/RT in patients with CHF. Twenty-five male patients with CHF completed a 6-month cardiac rehabilitation program of either a sham-IMT/AT/RT program (control group, 51.84 ± 4.56 years old, n1 = 13), or a real-IMT/AT/RT program (study group, 51.75 ± 4.73 years old, n2 = 12). Inclusion criteria were ischemic heart failure, New York Heart Association (NYHA) class II-III, and reduced ejection fraction. Outcome measures were PImax, VO2peak, resting heart rate (RHR), heart rate (HR) reserve, rate pressure product (RPP), left-ventricular ejection fraction, and Minnesota Living with Heart Failure Questionnaire (MLwHFQ). Absolute mean changes from baseline (Δ) in the outcome measures were statistically analyzed as independent outcomes. ΔPImax, ΔRHR, ΔHR reserve, and ΔMLwHFQ total score were significantly greater in the study group than in the control group (p < 0.05). In addition, ΔRPP showed an observed difference in favor of the study group with a tendency towards statistical significance (p = 0.07). IMT could be a successful complementary intervention to exercise-based cardiac rehabilitation programs comprising AT/RT, yielding greater improvements in PImax, RHR, HR reserve, and HRQoL in male patients with ischemic heart failure (NYHA class II-III).