In 1931, Portuguese angiography pioneers including Lopo de Carvalho and Egas Moniz performed conventional pulmonary angiography. The technique used contrast and X-rays to visualise the pulmonary arteries. It became a major diagnostic method for pulmonary embolism before CT pulmonary angiography.

The first pulmonary angiography performed in 1931 provided a new lens through which to view the human body, particularly the concept of breath. In literature, breath has long symbolized spirit and life, and this technology made the invisible struggles of existence more tangible.