Clinical study on the characteristics of exercise pathophysiological in patients with severe heart failure

Abstract

Objective: The cardiopulmonary function of patients with chronic heart failure (CHF) was severely limited, but the holistic integrative exercise pathophysiology is still unclear. Methods: After signed the consent form, Eighty three patients with severe CHF from October 2016 to October 2017 in Fuwai Hospital were performed Ramp incremental loading program CardioPulmonary Exercise Testing (CPET), and 12 normal subjects served as control. CPET were performed according to standard of Harbor-UCLA MC and the circulatory, respiratory and metabolic parameters during CPET were measured and analyzed. Results: Peak oxygen uptake (Peak VO2) in CHF (14.33±2.69) ml/(min·kg), (44.25±14.74)%pred was significantly lower than control ((29.42±5.46) ml/(min·kg), (83.88±6.28)%pred). Other core parameters of CPET such as anaerobic threshold (AT), peak oxygen pulse, oxygen uptake efficiency platform (OUEP), the lowest of carbon dioxide output ventilation ratio (Lowest VE/VCO2), and carbon dioxide output ventilation slope (VE/VCO2 Slope) in CHF were significantly different with the control group(P<0.01). The core parameters of lung function, such as forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, and carbon monoxide diffusion (DLCO) were significantly decreased (P<0.01). Systolic blood pressure during all stages of CPET in CHF was significantly lower than control group (P<0.05); Heart rate at AT, peak and recovery stages were significantly lower than control (P<0.01). Minute ventilation, tidal volume and respiratory frequency at rest, warm-up were significantly higher than control (P<0.05). Tidal volume at recovery was significantly higher than control (P<0.05). VO2 at AT, peak and recovery stages in CHF were significantly higher than control (P<0.01). Oxygen pulse at AT and peak were significantly higher than control (P<0.01). Pulse oxygen saturation during all stages of CPET in CHF were significantly lower than control (P<0.01). Conclusion: The decreased holistic functional capacity of cardiogenic CHF dominantly due to circulatory limitation, and secondly due to respiratory and metabolic limitation.