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Integration of Brain Tissue Saturation Monitoring in Cardiopulmonary Exercise Testing in Patients with Heart Failure
Published on: October 1, 2019
Would a right shift of the oxy-hemoglobin dissociation curve improve exercise capacity in patients with heart
Kisuk Min1, Dongwook Yeo2, Jeung-Ki Yoo3
1Department of Kinesiology, University of Texas at El Paso, El Paso 79968, TX, United States.
Abstract:
Exercise intolerance is a hallmark of symptoms in patients with heart failure. In addition to reduced cardiac output, a series of impairments in pulmonary and vascular systems leads to decreases in oxygen delivery and availability in locomotor muscles. This contributes to exercise intolerance in heart failure. The oxy-hemoglobin dissociation curve is essentially a graph illustrating the relationship between the partial pressure of oxygen (PO2, X-axis) and oxygen saturation (SaO2, Y-axis) of hemoglobin. The rightward shift of the curve indicates that hemoglobin's affinity for oxygen decreases and in turn, it may allow the release of more oxygen to tissues. In the present study, we discuss the pathophysiological impairment, which causes exercise intolerance in heart failure patients and suggest a strategy to improve exercise capacity without altering cardiac output via modulating the oxy-hemoglobin dissociation curve.
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