Implications of exercise-induced pulmonary arterial hypertension

Med Sci Sports Exerc. 2011 Jun;43(6):983-9. doi: 10.1249/MSS.0b013e318204cdac.

Abstract

Purpose: To characterize the hemodynamic and ventilatory responses to exercise in a group of patients with unexplained dyspnea, increased risk for pulmonary arterial hypertension (PAH), and an elevated mean pulmonary artery pressure (mPAP; >30 mm Hg) on exercise.

Methods: A total of 37 symptomatic patients at risk of PAH and 20 healthy controls underwent a cardiopulmonary exercise test and were assessed for quality of life (QOL). Patients had a pulmonary artery catheter in situ during the exercise test.

Results: Seventeen subjects had exercise-induced PAH (EIPAH), which we defined as mPAP ≤ 25 mm Hg at rest, and mPAP > 30 mm Hg and pulmonary artery wedge pressure <20 mm Hg on exercise. These subjects had reduced peak exercise cardiac output (72% ± 19% predicted). Further, compared with matched controls, subjects with EIPAH had reduced peak oxygen consumption (1.2 ± 0.4 vs 1.7 ± 0.5 L · min, P < 0.05), an elevated ventilatory equivalent for carbon dioxide (41.0 ± 7.3 vs 31.0 ± 2.9, P < 0.05) and reduced end-tidal carbon dioxide tension (32.6 ± 3.6 vs 39.4 ± 2.7 mm Hg, P < 0.05) at the anaerobic threshold. These exercise abnormalities were associated with impaired QOL (P < 0.05).

Conclusions: Elevated pulmonary artery pressure on exercise can be associated with hemodynamic and ventilatory abnormalities typical of PAH, along with impaired exercise capacity and reduced QOL.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age Factors
  • Carbon Dioxide / metabolism
  • Cardiac Output / physiology
  • Case-Control Studies
  • Catheters
  • Dyspnea / etiology
  • Exercise Test / adverse effects*
  • Exercise Tolerance / physiology
  • Female
  • Humans
  • Hypertension, Pulmonary / etiology*
  • Hypertension, Pulmonary / physiopathology*
  • Male
  • Middle Aged
  • Monitoring, Physiologic
  • Oxygen Consumption / physiology
  • Pulmonary Artery
  • Pulmonary Ventilation / physiology
  • Pulmonary Wedge Pressure / physiology
  • Quality of Life
  • Vascular Resistance / physiology

Substances

  • Carbon Dioxide