Impact of Integrative Cardiopulmonary Exercise Testing (17)
Furthermore, the maximum Vo2 in patients with chronic heart failure had a strong relationship with maximum cardiac index during treadmill exercise. Patients with maximum Vo2 greater than 20 ml/min/kg had cardiac index greater than 8 L/min/m2, whereas those with maximum Vo2 less than 10 ml/min/kg had maximum cardiac index less than 4 ml/m in/m2. Importantly, the maximum Vo2 was physiologically closely tied to the maximum cardiac output because 02 extraction during exercise in these patients was not abnormally reduced.
Of particular note, exercise capacity has been demonstrated to relate to mortality in the short term.
Chronic heart failure patients with maximum Vo2 less than 10 ml/min/kg had a 77 percent 12-month mortality, whereas those with maximum Vo2 between 10 and 18 ml/min/kg had a 14 percent mortality.
Trials of therapeutic agents based on improvement of such measurements as maximum Vo2 and AT have also demonstrated that there may be discrepancies between hemodynamic changes and changes in exercise performance. antibiotic levaquin
Some authors have emphasized the AT measurement in chronic heart failure patients. Simonton et al recently found good reproducibility of the AT measured by noninvasive gas exchange methods in patients with congestive heart failure.