OBJECTIVE To assess the change in peak oxygen consumption (pVO2) and determine its outcome predictors after aortic valve replacement (AVR) for aortic stenosis (AS). METHODS Patients with AS and preserved left ventricular ejection fraction who were referred for single AVR had cardiopulmonary exercise testing prior to and 9 months post-AVR. Predictors of outcome for pVO2 were determined by mult...

The pulmonary oxygen uptake (pVO2) kinetic response at the onset of exercise provides a noninvasive window into the metabolic activity of the muscle and a valuable means of increasing our understanding of developmental muscle metabolism. However, to date only limited research has been devoted to investigating the pVO2 kinetic response during exercise in children and adolescents. From the rigoro...

BACKGROUND Peak oxygen consumption (pVO2) reflects oxygen extraction from the skeletal muscles, but is routinely corrected for body weight. We hypothesized that correcting pVO2 for lean tissue rather than total body weight would improve the prediction of prognosis in patients with chronic heart failure (CHF). METHODS AND RESULTS A total of 272 CHF outpatients (mean age 61 +/- 12 years, New Yo...

OBJECTIVE To establish the prevalence of chronotropic incompetence in a cohort of patients with chronic heart failure (CHF) taking modern medications for heart failure, and whether this affected exercise capacity and predicted prognosis. METHODS Heart rate response to exercise was examined in 237 patients with CHF in sinus rhythm, who were compared with 118 control volunteers. The percentage ...

BACKGROUND Clinicians are sometimes advised to make decisions using thresholds in measured variables, derived from prognostic studies. OBJECTIVES We studied why there are conflicting apparently-optimal prognostic thresholds, for example in exercise peak oxygen uptake (pVO2), ejection fraction (EF), and Brain Natriuretic Peptide (BNP) in heart failure (HF). DATA SOURCES AND ELIGIBILITY CRITE...

REASONS FOR PERFORMING STUDY Alterations in cerebral haemodynamics may contribute to perianaesthetic complications in horses. Near-infrared spectroscopy (NIRS) is frequently used intraoperatively in man to provide information regarding cerebral perfusion. OBJECTIVES To determine whether NIRS can identify trends in regional cerebral oxygen saturation (rSO2) in horses and whether there is a cor...

Patients with moderate to severe aortic stenosis (AVA <1.3 cm2) who were judged, by a referring cardiologist, as asymptomatic or equivocal symptomatic from the aortic stenosis were included in the study. Patients with left ventricular ejection fraction <50% were not included. Twenty-nine percent of the referred patients were judged asymptomatic and 71% equivocal symptomatic from their valve dis...

Methods We randomized 35 patients with CHF (age 64 13 years, peak oxygen consumption [pVO2] 14.0 2.7 ml/kg/ min) to 16 weeks of intravenous iron (200 mg weekly until ferritin 500 ng/ml, 200 mg monthly thereafter) or no treatment in a 2:1 ratio. Ferritin was required to be 100 ng/ml or ferritin 100 to 300 ng/ml with transferrin saturation 20%. Patients were stratified according to hemoglobin lev...

Cardiopulmonary exercise testing (CPET) has long been shown to provide important prognostic information in patients with heart failure. Since the 1991 publication by Mancini et al, CPET, and specifically peak oxygen consumption (pVO2), has been used in prognostication for patients with heart failure being assessed for cardiac transplantation. pVO2 is essentially an assessment of cardiac reserve...

The purpose of this investigation was to determine the contribution of muscle O(2) consumption (mVO2) to pulmonary O(2) uptake (pVO2) during both low-intensity (LI) and high-intensity (HI) knee-extension exercise, and during subsequent recovery, in humans. Seven healthy male subjects (age 20-25 years) completed a series of LI and HI square-wave exercise tests in which mVO2 (direct Fick techniqu...