title: Age-related upper limits of normal for maximum upright exercise pulmonary haemodynamics.
abstract: The exercise definition of pulmonary hypertension was eliminated from the pulmonary hypertension guidelines in part due to uncertainty of the upper limits of normal (ULNs) for exercise haemodynamics in subjects >50 years old.The present study, therefore, evaluated the pulmonary haemodynamic responses to maximum upright incremental cycling exercise in consecutive subjects who underwent an invasive cardiopulmonary exercise testing for unexplained exertional intolerance, deemed normal based on preserved exercise capacity and normal resting supine haemodynamics. Subjects aged >50 years old (n=41) were compared with subjects ≤50 years old (n=25). ULNs were calculated as mean + 2 sdPeak exercise mean pulmonary arterial pressure was not different for subjects >50 and ≤50 years old (23 ± 5 versus 22 ± 4 mmHg, p=0.22), with ULN of 33 and 30 mmHg, respectively. Peak cardiac output was lower in older subjects (median (interquartile range): 12.1 (9.4-14.2)versus16.2 (13.8-19.2) L·min(-1), p<0.001). Peak pulmonary vascular resistance was higher in older subjects compared with younger subjects (mean ± sd: 1.20 ± 0.45 versus 0.82 ± 0.26 Wood units, p<0.001), with ULN of 2.10 and 1.34 Wood units, respectively.We observed that subjects >50 and ≤ 50 years old have different pulmonary vascular responses to exercise. Older subjects have higher pulmonary vascular resistance at peak exercise, resulting in different exercise haemodynamics ULNs compared with the younger population.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA Heart and Vascular Center, Brigham and Women's Hospital, Boston, MA, USA Division of Respiratory Diseases, Dept of Medicine, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil These authors contributed equally to the study.
authors.forename: Rudolf K F
authors.initials: RK
authors.lastname: Oliveira
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA Heart and Vascular Center, Brigham and Women's Hospital, Boston, MA, USA These authors contributed equally to the study.
authors.forename: Manyoo
authors.initials: M
authors.lastname: Agarwal
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA Heart and Vascular Center, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Tracy
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA Heart and Vascular Center, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Abbey L
authors.initials: AL
authors.lastname: Karin
authors.affiliation: Heart and Vascular Center, Brigham and Women's Hospital, Boston, MA, USA Dept of Cardiology, Boston Children's Hospital, Boston, MA, USA Division of Cardiovascular Medicine, Dept of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Opotowsky
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA Heart and Vascular Center, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Aaron B
authors.initials: AB
authors.lastname: Waxman
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Dept of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA Heart and Vascular Center, Brigham and Women's Hospital, Boston, MA, USA dsystrom@partners.org.
authors.forename: David M
authors.initials: DM
authors.lastname: Systrom
mesh_terms: D000328:Adult; D000368:Aged; D062186:Arterial Pressure; D001642:Bicycling; D002302:Cardiac Output; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D011651:Pulmonary Artery; D012146:Rest; D013318:Stroke Volume; D014655:Vascular Resistance / Q000502:physiology