title: Optimizing the evaluation of excess exercise ventilation for prognosis assessment in pulmonary arterial hypertension.
abstract: 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.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  Measurements of excessive exercise ventilation which consider all data points maximize the usefulness of incremental cardiopulmonary exercise testing in the prognosis evaluation of PAH.
authors.affiliation: Pulmonary 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.
authors.forename: Eloara V M
authors.initials: EV
authors.lastname: Ferreira
authors.affiliation: Pulmonary Vascular Group, Division of Respiratory Diseases, Department of Medicine, São Paulo School of Medicine (EPM), Federal University of Sao Paulo (UNIFESP), Brazil nederalb@gmail.com.
authors.forename: Jaquelina S
authors.initials: JS
authors.lastname: Ota-Arakaki
authors.affiliation: Pulmonary 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.
authors.forename: Roberta P
authors.initials: RP
authors.lastname: Ramos
authors.affiliation: Pulmonary Vascular Group, Division of Respiratory Diseases, Department of Medicine, São Paulo School of Medicine (EPM), Federal University of Sao Paulo (UNIFESP), Brazil.
authors.forename: Priscila B
authors.initials: PB
authors.lastname: Barbosa
authors.affiliation: Pulmonary Vascular Group, Division of Respiratory Diseases, Department of Medicine, São Paulo School of Medicine (EPM), Federal University of Sao Paulo (UNIFESP), Brazil.
authors.forename: Melline
authors.initials: M
authors.lastname: Almeida
authors.affiliation: Pulmonary 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.
authors.forename: Erika C
authors.initials: EC
authors.lastname: Treptow
authors.affiliation: Pulmonary Vascular Group, Division of Respiratory Diseases, Department of Medicine, São Paulo School of Medicine (EPM), Federal University of Sao Paulo (UNIFESP), Brazil.
authors.forename: Fabricio M
authors.initials: FM
authors.lastname: Valois
authors.affiliation: 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.
authors.forename: Luiz E
authors.initials: LE
authors.lastname: Nery
authors.affiliation: 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 Division of Respiratory and Critical Care Medicine, Department of Medicine, Queeńs University, Kingston, Canada.
authors.forename: J Alberto
authors.initials: JA
authors.lastname: Neder
mesh_terms: D000328:Adult; D062186:Arterial Pressure; D001938:Brazil; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D018450:Disease Progression; D018572:Disease-Free Survival; D005080:Exercise Test; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D053208:Kaplan-Meier Estimate; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000503:physiopathology*; D012123:Pulmonary Ventilation; D012307:Risk Factors; D013147:Spirometry; D062606:Tertiary Care Centers; D013997:Time Factors; D055815:Young Adult
keywords: Exertion; exercise testing; prognosis; pulmonary hypertension; ventilation