Exaggerated hypoxic pulmonary vasoconstriction without susceptibility to high altitude pulmonary edema

High Alt Med Biol. 2015 Mar;16(1):11-7. doi: 10.1089/ham.2014.1117.


Background: Abnormally high pulmonary artery pressure (PAP) in hypoxia due to exaggerated hypoxic pulmonary vasoconstriction (HPV) is a key factor for development of high-altitude pulmonary edema (HAPE). It was shown that about 10% of a healthy Caucasian population has an exaggerated HPV that is comparable to the response measured in HAPE-susceptible individuals. Therefore, we hypothesized that those with exaggerated HPV are HAPE-susceptible.

Methods and results: We screened 421 healthy Caucasians naïve to high altitude for HPV using Doppler echocardiography for assessment of systolic PAP in normobaric hypoxia (PASPHx; Po2 corresponding to 4500 m). Subjects with exaggerated HPV and matched controls were exposed to 4559 m with an identical protocol that causes HAPE in 62% of HAPE-S. Screening revealed 39 subjects with exaggerated HPV, of whom 33 (PASPHx 51±6 mmHg) ascended within 24 hours to 4559 m. Four (13%) of them developed HAPE during the 48 h-stay. This incidence is significantly lower than the recurrence rate of 62% previously observed in HAPE-S in the same setting. None of the control subjects (PASPHx 33±5 mmHg) developed HAPE.

Conclusion: An exaggerated HPV cannot be considered a surrogate maker for HAPE-susceptibility although excessively elevated PAP is a hallmark in HAPE, while a normal HPV appears to protect from HAPE in this study.

Trial registration: ClinicalTrials.gov NCT00559442.

Keywords: high-altitude pulmonary edema; hypoxia; pulmonary vasoconstriction.

Publication types

  • Clinical Study

MeSH terms

  • Adult
  • Altitude
  • Altitude Sickness / epidemiology
  • Altitude Sickness / etiology*
  • Arterial Pressure
  • Case-Control Studies
  • Disease Susceptibility
  • Humans
  • Hypertension, Pulmonary / epidemiology
  • Hypertension, Pulmonary / etiology*
  • Hypoxia / complications*
  • Lung / blood supply
  • Middle Aged
  • Pulmonary Artery / physiopathology*
  • Time Factors
  • Vasoconstriction*
  • White People

Supplementary concepts

  • Pulmonary edema of mountaineers

Associated data

  • ClinicalTrials.gov/NCT00559442