ABSTRACT
The second World Symposium on Pulmonary Hypertension (WSPH) held in Evian, France, in 1998, proposed a Classification of Pulmonary Hypertension (PH) and the issue of Chronic High Altitude Exposure was incorporated for the first time as a subcategory of group 3 named “PH associated to Lung Diseases and/ or Hypoxemia.” This topic was preserved in the updated classifications of the following WSPHs including the last one held in Nice, France, in 2013. However, the issue of Chronic High Altitude Exposure was never discussed at such meetings, and the chapter on Diagnosis and Assessment of PH was mainly devoted to Pulmonary Arterial Hypertension (PAH) and other diseases associated to PH. Definition of PH is another major topic
discussed during the WSPHs, and the diagnostic criterion for PH was initially based on the values of pulmonary arterial pressure (PAP), often mixed data from right heart catheterization (RHC) and transthoracic echocardiography (TTE) that resulted from the expert opinion and registries mainly related to PAH. The fourth WSPH proposed a new criterion for PH based on available evidence that resulted from a literature review carried out by Kovacs et al (1) who analyzed the data of 47 studies and 1187 healthy volunteers who were studied with RHC at rest and during physical exercise. The average resting mPAP was 14 ± 3 mm Hg, and consequently, an upper limit of 20 mm Hg (mean + 2SD) for healthy people. This diagnostic criterion, supported by the fourth WSPH, will be used in this chapter as a reference term for studies performed with RHC. For studies on PH carried out
Introduction 454 Chronic high-altitude exposure and pulmonary
hypertension 455 Healthy highlanders 455 Asymptomatic postnatal pulmonary hypertension 455 Combined influence of age and altitude on the
pulmonary arterial pressure 456 Pulmonary hypertension as related to high-altitude
ancestry 457 Chronic mountain sickness 457 Definition, pathogenesis, and classification 457 Clinical picture 458 Invasive and noninvasive studies at rest in
highlanders with and without CMS 459 Right heart catheterization studies 459 Doppler echocardiographic studies 460 Invasive and noninvasive studies during exercise in
highlanders with and without CMS 461 Right heart catheterization studies 461 Doppler echocardiographic studies 462
High-altitude heart disease (China) 463 Definition and clinical picture 463 Pulmonary hemodynamics 463 High altitude cor pulmonale (Kyrgyzstan) 464 Definition and clinical picture 464 Pulmonary hemodynamics 464 Reappraisal of the consensus on chronic high-altitude
diseases 464 Background 464 Classification of chronic high-altitude diseases 464 Scoring system for diagnosis of chronic mountain
sickness 465 Hemoglobin threshold values 465 Hypoxemia levels 465 Pulmonary hypertension 465 Limitations and expansion of the scoring system for
diagnosis of CMS 465 Prevention and treatment of chronic mountain sickness 465 References 466
with TTE, we use as a reference the classical and extensive study of McQuillan et al (2) and the recent paper of D’Andrea et al (3). Both publications provide normal values, quite similar, for healthy people grouped for age decades.
