title: The pulmonary artery wedge pressure response to sustained exercise is time-variant in healthy adults.
abstract: OBJECTIVE
  The clinical and prognostic significance of 'exaggerated' elevations in pulmonary artery wedge pressure (PAWP) during symptom-limited exercise testing is increasingly recognised. However, the paucity of normative data makes the identification of abnormal responses challenging. Our objectives was to describe haemodynamic responses that reflect normal adaptation to submaximal exercise in a group of community-dwelling, older, non-dyspnoeic adults.
  
  
  METHODS
  Twenty-eight healthy volunteers (16 men/12 women; 55±6 years) were studied during rest and two consecutive stages of cycle ergometry, at targeted heart rates of 100 bpm (light exercise) and 120 bpm (moderate exercise). Right-heart catheterisation was performed to measure pulmonary artery pressures, both early (2 min) and after sustained (7 min) exercise at each intensity.
  
  
  RESULTS
  End-expiratory PAWP at baseline was 11±3 mm Hg and increased to 22±5 mm Hg at early-light exercise (p<0.01). At sustained-light exercise, PAWP declined to 17±5 mm Hg, remaining elevated versus baseline (p<0.01). PAWP increased again at early-moderate exercise to 20±6 mm Hg but did not exceed the values observed at early-light exercise, and declined further to 15±5 mm Hg at sustained-moderate exercise (p<0.01 vs baseline). When analysed at 30 s intervals, mean and diastolic pulmonary artery pressures peaked at 180 (IQR=30) s and 130 (IQR=90) s, respectively, and both declined significantly by 420 (IQR=30) s (both p<0.01) of light exercise. Similar temporal patterns were observed at moderate exercise.
  
  
  CONCLUSIONS
  The range of PAWP responses to submaximal exercise is broad in health, but also time-variant. PAWP may routinely exceed 20 mm Hg early in exercise. Initial increases in PAWP and mean pulmonary artery pressures do not necessarily reflect abnormal cardiopulmonary physiology, as pressures may normalise within a period of minutes.
authors.affiliation: Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada Division of Cardiology, Mount Sinai Hospital/University Health Network, Toronto, Ontario, Canada.
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Wright
authors.affiliation: Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada Division of Cardiology, Mount Sinai Hospital/University Health Network, Toronto, Ontario, Canada.
authors.forename: Sam
authors.initials: S
authors.lastname: Esfandiari
authors.affiliation: Department of Exercise Sciences, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Taylor
authors.initials: T
authors.lastname: Gray
authors.affiliation: Division of Cardiology, Mount Sinai Hospital/University Health Network, Toronto, Ontario, Canada.
authors.forename: Felipe C
authors.initials: FC
authors.lastname: Fuchs
authors.affiliation: Division of Cardiology, Mount Sinai Hospital/University Health Network, Toronto, Ontario, Canada.
authors.forename: Anjala
authors.initials: A
authors.lastname: Chelvanathan
authors.affiliation: Division of Cardiology, Mount Sinai Hospital/University Health Network, Toronto, Ontario, Canada.
authors.forename: William
authors.initials: W
authors.lastname: Chan
authors.affiliation: Division of Cardiology, Mount Sinai Hospital/University Health Network, Toronto, Ontario, Canada.
authors.forename: Zion
authors.initials: Z
authors.lastname: Sasson
authors.affiliation: Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada Division of Respirology, University Health Network, Toronto, Ontario, Canada.
authors.forename: John T
authors.initials: JT
authors.lastname: Granton
authors.affiliation: Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada Division of Cardiology, Mount Sinai Hospital/University Health Network, Toronto, Ontario, Canada Department of Exercise Sciences, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Jack M
authors.initials: JM
authors.lastname: Goodman
authors.affiliation: Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada Division of Cardiology, Mount Sinai Hospital/University Health Network, Toronto, Ontario, Canada.
authors.forename: Susanna
authors.initials: S
authors.lastname: Mak
mesh_terms: D000375:Aging / Q000502:physiology*; D006328:Cardiac Catheterization; D005080:Exercise Test / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000502:physiology*; D011669:Pulmonary Wedge Pressure / Q000502:physiology*