Chen sign

Chen sign on chest radiography is the prominence of the left basal pulmonary vasculature, compared to the right, seen in valvular pulmonary stenosis. It is due to the asymmetric increase in pulmonary blood flow to the left lung due to preferential blood flow into the left pulmonary artery after passing through the stenosed pulmonary valve during systole. The left pulmonary artery may be dilated due to post stenotic effects.

History and etymology

It is named after James TT Chen, (1925-2006) a Chinese-American cardiothoracic radiologist who was a Professor at Duke University Medical Center.