Exercise Periodic Breathing Impairs Functional Capacity by Reducing the Ventilatory‐Hemodynamic Efficiency in Patients with Heart Failure

Abstract

This investigation elucidated how exercise periodic breathing (EPB) influences functional capacity by modulating the ventilatory‐hemodynamic efficiency in patients with heart failure (HF). Ninety‐eight HF patients with (n=45) or without (n=43) EPB performed an incremental exercise test using a bicycle ergometer. A noninvasive bio‐reactance device was applied to measure cardiac hemodynamics, and a near‐infrared spectroscopy was employed to assess perfusion in frontal cerebral lobe and vastus lateralis muscle. Compared to non‐EPB counterparts, the patients with EPB revealed (i) smaller VO2peak and oxygen uptake efficiency slopes (OUES) and greater VE‐VO2 slopes; (ii) less cardiac output (QH) and perfusions in the frontal cerebral lobe (QC) and vastus lateralis muscle (QM) during exercise; and (iii) lower the score of the Short Form‐36 physical component and higher the score of the Minnesota Living with Heart Failure questionnaire. Peak QH, QC, and QM levels were directly related the OUES and VO2peak, and inversely related to the VE‐VCO2 slope. In multivariate analysis, the VE‐VCO2 slope was an effect modifier, which modulated the correlation between the Short Form‐36 physical score and central/peripheral hemodynamics. Therefore we conclude that EPB may reduce the ventilatory‐hemodynamic efficiency during exercise, thereby impairing functional capacity in patients with HF.