Heart failure (HF) is a complex syndrome characterized by myocardial dysfunction and an
impaired regulatory function of multiple organ systems which were resulted from impaired
cardiac output and consequently impaired perfusion of target organ. In cardiopulmonary
exercise test (CPET), the investigators found there is periodic oscillation in minute
ventilation of some patient. With periodic breathing (PB), clear oscillations in oxygen
uptake, carbon dioxide output, tidal volume and left ventricle ejection fraction (LVEF) were
also noted. Exertional hyper-ventilation that is caused by HF may further induce
vasoconstriction during exercise and lead to further dysfunction of end-organ and muscle.
Reduced end-organ perfusion/oxygenation may critically limit exercise performance. Hypoxic
change during nadir phase of PB may deteriorate the exercise limitation. Physical training
can have beneficial effects which can effectively counteract the progression of deleterious
compensatory mechanisms of HF. Whether exercise yields the same beneficial effect on
ventilation oscillation and inefficacy is not clear.
The investigators will observe the real-time cardiac and hemodynamic change respond to
exercise with periodic breathing change. The investigators expect that these results obtained
from this study can aid in determining appropriate exercise intervention to improve aerobic
fitness as well as simultaneously improve hemodynamic control in patients with HF. A
quasi-experimental design will be used in this investigation. 60 HF patients will be
recruited from Chang Gung Medical Foundation, Keelung Branch after they have provided
informed consent. These subjects will be divided into PB (n=30) and non-PB groups (n=30) by
their expression of CPET. Patients from each groups received the same therapy and trace
course for 2years including CV clinics, CPET and polysomnography. The investigators will
measure subjects' physical fitness, oxygen transport and utilization of exercising skeletal
muscles, cardiovascular functions and hemodynamics, blood cell parameters, RBC deformity and
aggregation, plasma biomarkers of myocardial damage, oxygen stress and quality of life at
pre-training stage and following the 6th , 12th, 18th, 24th months of the tracing program.
Experimental results were analyzed by descriptive statistics, independent t-test, and
repeated measure ANOVA. The investigators study the above parameter to realize the
physiological response to exercise of these patients and discover the appropriate exercise
intensity for prescription for EPB.