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Updated: May 10, 2026
Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
Published on: February 20, 2017
Optimizing the evaluation of excess exercise ventilation for prognosis assessment in pulmonary arterial hypertension
Eloara V M Ferreira1, Jaquelina S Ota-Arakaki2, Roberta P Ramos1
1Pulmonary Vascular Group, Division of Respiratory Diseases, Department of Medicine, São Paulo School of Medicine (EPM), Federal University of Sao Paulo (UNIFESP), Brazil Pulmonary Function and Clinical Exercise Physiology Unit, Division of Respiratory Diseases, Department of Medicine, São Paulo School of Medicine (EPM), Federal University of Sao Paulo (UNIFESP), Brazil.
Background:
Increased ventilatory (.VE) response to carbon dioxide output (.VCO2) is a key finding of incremental cardiopulmonary exercise testing in both heart failure and pulmonary arterial hypertension (PAH). As with heart failure, measures of excessive exercise ventilation considering high-to-peak exercise .VE-VCO2 might have higher prognostic relevance than those restrained to sub-maximal exercise in PAH.
Design:
Cross-sectional and observational study on a tertiary center.
Methods:
Eighty-four patients (36 idiopathic and 48 with associated conditions) were followed up for up to five years. Excessive exercise ventilation was calculated as a slope (Δ .VE/Δ .VCO2 to the respiratory compensation point (RCP) and to exercise cessation (PEAK)) and as a ratio (.VE-VCO2 at the anaerobic threshold (AT) and at PEAK).
Results:
Thirteen patients died and three had atrial septostomy. Multivariable regression analyses revealed that Δ .VE/Δ .VCO2(PEAK) <55 and .VE/.VCO2(PEAK) <57 were better related to prognosis than Δ .VE/Δ .VCO2(RCP) and .VE/.VCO2(AT) (p < 0.01). Δ oxygen uptake (.VO2)/Δ work rate >5.5 ml/min per W was the only other independent prognostic index. According to a Kaplan-Meier survival analysis, 96.9% (90.8% to 100%) of patients showing Δ .VE/Δ .VCO2(PEAK) <55 and Δ .VO2/Δ work rate >5.5 ml/min per W were free from a PAH-related event. In contrast, 74.7% (70.1% to 78.2%) with both parameters outside these ranges had a negative outcome.
Conclusion:
Measurements of excessive exercise ventilation which consider all data points maximize the usefulness of incremental cardiopulmonary exercise testing in the prognosis evaluation of PAH.
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