title: Exercise induces rapid interstitial lung water accumulation in patients with chronic mountain sickness.
abstract: BACKGROUND
  Chronic mountain sickness (CMS) is a major public health problem in mountainous regions of the world. In its more advanced stages, exercise intolerance is often found, but the underlying mechanism is not known. Recent evidence indicates that exercise-induced pulmonary hypertension is markedly exaggerated in CMS. We speculated that this problem may cause pulmonary fluid accumulation and aggravate hypoxemia during exercise.
  
  
  METHODS
  We assessed extravascular lung water (chest ultrasonography), pulmonary artery pressure, and left ventricular function in 15 patients with CMS and 20 control subjects at rest and during exercise at 3,600 m.
  
  
  RESULTS
  Exercise at high altitude rapidly induced pulmonary interstitial fluid accumulation in all patients but one (14 of 15) with CMS and further aggravated the preexisting hypoxemia. In contrast, in healthy high-altitude dwellers exercise did not induce fluid accumulation in the majority of subjects (16 of 20) (P = .002 vs CMS) and did not alter arterial oxygenation. Exercise-induced pulmonary interstitial fluid accumulation and hypoxemia in patients with CMS was accompanied by a more than two times larger increase of pulmonary artery pressure than in control subjects (P < .001), but no evidence of left ventricular dysfunction. Oxygen inhalation markedly attenuated the exercise-induced pulmonary hypertension (P < .01) and interstitial fluid accumulation (P < .05) in patients with CMS but had no detectable effects in control subjects.
  
  
  CONCLUSIONS
  To our knowledge, these findings provide the first direct evidence that exercise induces rapid interstitial lung fluid accumulation and hypoxemia in patients with CMS that appear to be related to exaggerated pulmonary hypertension. We suggest that this problem contributes to exercise intolerance in patients with CMS.
  
  
  BACKGROUND
  ClinicalTrials.gov; No.: NCT01182792; URL: www.clinicaltrials.gov.
authors: Institute of Clinical Physiology, Pisa, Italy.
authors: Lorenza
authors: L
authors: Pratali
authors: Department of Cardiology, University Hospital of Bern, Bern, Switzerland; Department of Internal Medicine and Botnar Center for Clinical Research, Lausanne, Switzerland.
authors: Stefano F
authors: SF
authors: Rimoldi
authors: Department of Internal Medicine and Botnar Center for Clinical Research, Lausanne, Switzerland.
authors: Emrush
authors: E
authors: Rexhaj
authors: Department of Cardiology, University Hospital of Bern, Bern, Switzerland.
authors: Damian
authors: D
authors: Hutter
authors: Institute of Clinical Physiology, Pisa, Italy.
authors: Francesco
authors: F
authors: Faita
authors: Instituto Boliviano de Biologia de Altura, La Paz, Bolivia.
authors: Carlos Salinas
authors: CS
authors: Salmòn
authors: Instituto Boliviano de Biologia de Altura, La Paz, Bolivia.
authors: Mercedes
authors: M
authors: Villena
authors: Institute of Clinical Physiology, Pisa, Italy.
authors: Rosa
authors: R
authors: Sicari
authors: Institute of Clinical Physiology, Pisa, Italy.
authors: Eugenio
authors: E
authors: Picano
authors: Department of Cardiology, University Hospital of Bern, Bern, Switzerland.
authors: Yves
authors: Y
authors: Allemann
authors: Department of Cardiology, University Hospital of Bern, Bern, Switzerland; Facultad de Ciencias, Departamento de Biología, Universidad de Tarapacá, Arica, Chile.
authors: Urs
authors: U
authors: Scherrer
authors: Department of Internal Medicine and Botnar Center for Clinical Research, Lausanne, Switzerland. Electronic address: claudio.sartori@chuv.ch.
authors: Claudio
authors: C
authors: Sartori
mesh_terms: D000532:Altitude Sickness / Q000503:physiopathology* / Q000628:therapy; D002908:Chronic Disease; D004452:Echocardiography; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D015633:Extravascular Lung Water / Q000378:metabolism*; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000209:etiology / Q000628:therapy; D000860:Hypoxia / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010102:Oxygen Inhalation Therapy; D014463:Ultrasonography