Dynamics of Oxygen Uptake for Submaximal Exercise and Recovery in Patients With Chronic Heart Failure

Breathing Intolerance Index and Control of Ventilation, a Non-invasive Method for Evaluating Inspiratory Muscle Endurance at Rest and Exercise, in Patients with Cardiomyopathy: One Year Follow-up

“…They determined that OUEP was the strongest predictor of early mortality. We previously reported that median peak V'O 2 for patients with chronic heart failure was 54% lower than in control subjects [9], similar to findings by Sietsema et al [22] who showed that peak V'O 2 (corrected for weight) was 62% lower than in normal control subjects. Since BIT was not significantly different between normal control subjects and those with heart failure, median V'O 2 /BIT was 46% that of healthy controls, similar to changes in V'O 2 / V' E described by Sun et al [28].…”

“…These authors reported an increase in peak V'O 2 amounting to 1.35 ml/kg/ min, or 6.4% of the baseline value, similar to the increase (amounting to 10.5%) we found. Patients with chronic (stable) heart failure exhibit decreased maximal exercise capacity and slower transitions to and from submaximal levels of exercise [22][23][24]. Peak V'O 2 is a reliable indicator of prognosis in heart failure (but recently has been superseded by the slope of V'CO 2 /V' E , and relates to cardiac output and muscle perfusion [25].…”

Exercise capacity and impact of exercise training in patients after a Fontan procedure: A review

“…Nevertheless, this long-term decline in exercise tolerance following the procedure may also be related to the disease progression (17) or to the reduced capacity to increase the cardiac output (Q) in response to exercise secondary to the Fontantype circulation, thus limiting the oxygen transport to the periphery (22,23). Slower oxygen uptake kinetics, ie, the precise integration of the cardiorespiratory system required to transport the oxygen from the atmosphere through active muscles to achieve oxidative phosphorylation (24), is well documented in patients with coronary artery disease, cyanotic congenital heart disease or heart failure (25)(26)(27)(28)(29)(30)(31). In patients who have had a Fontan procedure, slower oxygen uptake kinetics was observed compared with those of healthy individuals, suggesting alterations in the central component (oxygen transport) and/or in the peripheral component (oxygen utilization) during exercise (32).…”

Kinetics of Pulmonary Gas Exchange During and While Recovering From Exercise in Patients After Anterior Myocardial Infarction

“…25 Therefore, interest has focused on the usefulness of the time constants of gas exchange kinetics during submaximal exercise. 3,[7][8][9][10][11][12][13] If the work rate is mild to moderate, gas exchange kinetics can be characterized by a single exponential equation. 5,26 During high-intensity exercise, these kinetics become more complex, and a multiexponential fitting equation may be more suitable for analyzing kinetics.…”