Pulmonary arterial enlargement in patients with acute exacerbation of interstitial pneumonia

The purpose of this study was to evaluate change in the size of the main pulmonary (PA) artery in patients with acute exacerbation of interstitial pneumonia (IP). Twenty-nine patients underwent computed tomography at baseline and at the time of acute IP exacerbation for the measurement of the diameters of the main PA and the ascending aorta. We found that the diameter of the main PA was significantly larger at the time of acute IP exacerbation than at baseline, which might reflect the alterations in pulmonary circulation.