Enlargement of the right descending pulmonary artery in pulmonary embolism.

Pulmonary embolism often is undetected during life, even though adequate diagnostic procedures are available, probably because the condition is not suspected. Chest radiographs were reviewed for changes in the right descending pulmonary artery in 73 patients with confirmed pulmonary embolism and in 85 in whom the original suspicion subsequently was not confirmed. In embolic patients, the vessel, measured at four different levels starting from the superior venous angle, was larger during acute embolization than some weeks later. In particular, the two proximal diameters of descending pulmonary artery were significantly enlarged ( p