Radiographic and hemodynamic changes during recovery from high-altitude pulmonary edema.

It has been suggested that accentuated pulmonary hypertension is a contributing factor in the development of high-altitude pulmonary edema (HAPE). The purpose of this study was to evaluate the chest radiographic features associated with pulmonary hemodynamic changes in HAPE. We studied 16 patients with HAPE using posteroanterior chest roentgenograms taken in the standing position both on admission and following recovery. The cardiothoracic ratio (CTR) as well as the area and volume of the main pulmonary artery were measured. During HAPE, we found slight enlargement of the CTR, especially the right ventricle, and prominence of the main pulmonary artery. These abnormalities significantly improved in the recovery state. The changes in area and volume of the main pulmonary artery were closely correlated with a decrease in CTR during recovery from HAPE, and correlated with the pulmonary hemodynamic changes observed by right heart catheterization (n = 4). Radiographic changes reflect the alterations in pulmonary hemodynamics in patients with HAPE.