title: Factors affecting the response to exercise in patients with severe pulmonary arterial hypertension.
abstract: BACKGROUND
  Ergospirometry objectively quantifies exercise capacity. Up until now, the response to exercise evaluated by ergospirometry in patients with pulmonary arterial hypertension has only been described in recently diagnosed.patients. Our aim is to describe the response to exercise in patients with severe pulmonary arterial hypertension under specific treatment and define which parameters determine their exercise capacity.
  
  
  METHODS
  A cross-sectional study was performed on 80 patients, 57 women, aged 45 (14), with severe pulmonary arterial hypertension (48 idiopathic, 14 related to toxic rapeseed oil, 13 to connective tissue disease, 5 to human immunodeficiency virus), mean pulmonary pressure at diagnosis 61(15)mmHg and after 49(33) months under treatment since diagnosis. Biomarkers were measured and echocardiography and ergospirometry were performed the same day.
  
  
  RESULTS
  Our patients, under specific treatment, showed the typical behaviour of patients with pulmonary arterial hypertension with less limitation of both aerobic capacity and ventilatory efficiency. Being male (p=0.004), high ventilatory equivalent for carbon dioxide at anaerobic threshold (p<0.001) or biomarkers (p=0.006) were the strongest predictors of impaired peak oxygen uptake in multivariate analysis, whereas for an impaired percentage achieved of predicted value were right ventricle diastolic diameter (p<0.001), months of treatment (p=0.01) and high ventilatory equivalent for CO(2) (p<0.001).
  
  
  CONCLUSIONS
  In pulmonary arterial hypertension, right ventricle dysfunction (expressed by its dilation or high NTproBNP) and impaired ventilatory inefficiency as well as being male or a short time under treatment can be considered as determining factors of impaired exercise capacity.
authors.affiliation: Servicio de Cardiología, Unidad de Insuficiencia Cardíaca, Hipertensión Pulmonar y Trasplante Cardíaco, H.U. 12 de Octubre, Red de Investigación Cooperativa del Ministerio de Sanidad y Consumo de España, Madrid, Spain. angelaflox@gmail.com
authors.forename: Angela
authors.initials: A
authors.lastname: Flox-Camacho
authors.forename: Pilar
authors.initials: P
authors.lastname: Escribano-Subías
authors.forename: Carmen
authors.initials: C
authors.lastname: Jiménez-López Guarch
authors.forename: Almudena
authors.initials: A
authors.lastname: Fernández-Vaquero
authors.forename: Dolores
authors.initials: D
authors.lastname: Martín-Ríos
authors.forename: Carlos Sáenz
authors.initials: CS
authors.lastname: de la Calzada-Campo
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005080:Exercise Test; D065627:Familial Primary Pulmonary Hypertension; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology / Q000628:therapy; D008297:Male; D015999:Multivariate Analysis; D012720:Severity of Illness Index; D013147:Spirometry