title: Detection of exercise-induced pulmonary arterial hypertension by cardiopulmonary exercise testing.
abstract: BACKGROUND
  The pulmonary arterial pressure (PAP) response to exercise may provide a tool for the early detection of pulmonary arterial hypertension (PAH). Therefore, an accurate noninvasive method for evaluating exercise-induced PAH (EIPAH) is desirable.
  
  
  OBJECTIVE
  We sought to examine if cardiopulmonary exercise testing (CPET) is able to indicate EIPAH.
  
  
  METHODS
  Fifty-three patients aged 67.1 ± 1.7 years (37 female, 16 male) with borderline PAH (resting mean PAP 21-24 mm Hg) performed CPET and right heart catheterization at rest and during handgrip testing.
  
  
  RESULTS
  When comparing patients with an exercise-induced mean PAP ≥ mm Hg (group A, n = 24) and subjects with an exercise-induced mean PAP <35 mm Hg (group B, n = 29), group A had a significantly lower mean aerobic capacity (15.2 ± 1.2 vs 19.7 ± 1.2 mL/min/kg; P = 0.02), higher ventilatory equivalents for oxygen at the anaerobic threshold (34.3 ± 1.5 vs 29.9 ± 1.1; P = 0.02), a widening of the mean alveolar-arterial oxygen difference (37.8 ± 3.0 vs 26.8 ± 2.4 mm Hg; P = 0.007), an elevated mean functional dead space ventilation (29.5 ± 2.7 vs 21.2 ± 1.7%; P = 0.008), and a higher mean arterial to end-tidal carbon dioxide gradient at peak exercise (3.7 ± 0.9 vs 0.4 ± 0.8 mm Hg; P = 0.007).
  
  
  CONCLUSIONS
  EIPAH is characterized by a decreased ventilatory efficiency due to ventilation to perfusion inequalities. CPET may be useful for the identification of EIPAH and serve to diagnose PAH at an early stage.
authors.affiliation: Department of Internal Medicine I, Klinikum Augsburg, Ludwig-Maximilians-University, Munich, Germany. martin.schwaiblmair@klinikum-augsburg.de
authors.forename: Martin
authors.initials: M
authors.lastname: Schwaiblmair
authors.forename: Christian
authors.initials: C
authors.lastname: Faul
authors.forename: Wolfgang
authors.initials: W
authors.lastname: von Scheidt
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Berghaus
mesh_terms: D000368:Aged; D015308:Anaerobic Threshold; D006328:Cardiac Catheterization; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D065627:Familial Primary Pulmonary Hypertension; D005260:Female; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis*; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*