Related Experiment Video
Updated: Jul 9, 2026
Dual Test Gas Pulmonary Diffusing Capacity Measurement During Exercise in Humans Using the Single-Breath Method
Published on: February 2, 2024
Combining the ventilatory response to exercise and peak oxygen consumption is no better than peak oxygen consumption
Lee Ingle1, Klaus K Witte, John G F Cleland
1Carnegie Research Institute, Leeds Metropolitan University, Leeds, UK.
Background:
A low peak oxygen uptake (pVO(2)) and steep VE/VCO(2) slope are independently associated with a worse prognosis in patients with chronic heart failure (CHF). We wished to confirm whether combining these variables as a ratio would lead to a more accurate predictor of prognosis than using either alone.
Methods:
388 CHF patients completed a treadmill-based cardiopulmonary exercise test (CPET) to volitional exhaustion using a modified Bruce protocol.
Results:
212 CHF patients completed the CPET with a peak RER >or= 1.0. Of these, 48 patients died and one was transplanted during follow-up. In surviving patients, the median follow-up period was 42 months (IQR 34-49 months). The ratio VE/VCO(2) slope/pVO(2) was calculated for each individual and its ability to predict outcome compared with other variables. The Cox multivariable survival analysis showed that pVO(2) was the strongest independent predictor of mortality in CHF patients.
Conclusion:
Our study shows that the composite variable VE/VCO(2) slope/pVO(2) is a less effective prognosticator than pVO(2) alone in patients with CHF.
More Related Videos
07:09Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
Published on: February 20, 2017
04:20Integration of Brain Tissue Saturation Monitoring in Cardiopulmonary Exercise Testing in Patients with Heart Failure
Published on: October 1, 2019
Related Concept Videos
01:20Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
01:17Exercise and Cardiac Output
Sustained exercise increases the muscles' oxygen demand, which can be met...
01:22Respiratory Volumes and Capacities
01:20Assessment of Ventilation I: Respiratory Rate
A Ventilation assessment is critical for monitoring a patient's health status. Respiration, one of the most accessible vital signs, provides insights into the function of numerous body systems and can indicate serious health issues, such as brainstem injuries from head trauma.
Critical Guidelines for Assessing Ventilation:
01:24Respiratory Capacities
One key metric is the Inspiratory Capacity (IC), which represents the maximum amount of air that can be inhaled with full effort. IC is calculated by summing the tidal volume and inspiratory reserve volume, typically ranging from 2.4 to 3.6 liters.
The Functional Residual Capacity (FRC) represents the air in the...
01:19Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...